feat(cli): Adding JUnit test reports (#19747)

This commit makes the following changes
- Created a `CompoundTestReporter` to allow us to use multiple reporters
- Implements `JUnitTestReporter` which writes JUnit XML to a path
- Added a CLI flag/option `--junit` that enables JUnit reporting. By
default this writes the report to `stdout` (and disables pretty
reporting). If a path is provided, it will write the JUnit report to
that file while the pretty reporter writes to stdout like normal

Output of `deno -- test --allow-all --unstable
--location=http://js-unit-tests/foo/bar --junit
cli/tests/unit/testing_test.ts `
```xml
<?xml version="1.0" encoding="UTF-8"?>
<testsuites name="deno test" tests="7" failures="0" errors="0" time="0.176">
    <testsuite name="file:///Users/cooper/deno/deno/cli/tests/unit/testing_test.ts" tests="7" disabled="0" errors="0" failures="0">
        <testcase name="testWrongOverloads" time="0.012">
        </testcase>
        <testcase name="nameOfTestCaseCantBeEmpty" time="0.009">
        </testcase>
        <testcase name="invalidStepArguments" time="0.008">
        </testcase>
        <testcase name="nameOnTextContext" time="0.029">
            <properties>
                <property name="step[passed]" value="step ... nested step"/>
                <property name="step[passed]" value="step"/>
            </properties>
        </testcase>
        <testcase name="originOnTextContext" time="0.030">
            <properties>
                <property name="step[passed]" value="step ... nested step"/>
                <property name="step[passed]" value="step"/>
            </properties>
        </testcase>
        <testcase name="parentOnTextContext" time="0.030">
            <properties>
                <property name="step[passed]" value="step ... nested step"/>
                <property name="step[passed]" value="step"/>
            </properties>
        </testcase>
        <testcase name="explicit undefined for boolean options" time="0.009">
        </testcase>
    </testsuite>
</testsuites>
```

1 files changed, 82 insertions, 0 deletions

diff --git a/cli/args/flags.rs b/cli/args/flags.rs
index d06a17a06..3f4498dac 100644
--- a/cli/args/flags.rs
+++ b/cli/args/flags.rs
@@ -221,6 +221,7 @@ pub struct TestFlags {
   pub concurrent_jobs: Option<NonZeroUsize>,
   pub trace_ops: bool,
   pub watch: Option<WatchFlags>,
+  pub junit_path: Option<String>,
 }
 
 #[derive(Clone, Debug, Eq, PartialEq)]
@@ -1848,6 +1849,16 @@ Directory arguments are expanded to all contained files matching the glob
     )
     .arg(no_clear_screen_arg())
     .arg(script_arg().last(true))
+    .arg(
+      Arg::new("junit")
+        .long("junit")
+        .value_name("PATH")
+        .value_hint(ValueHint::FilePath)
+        .help("Write a JUnit XML test report to PATH. Use '-' to write to stdout which is the default when PATH is not provided.")
+        .num_args(0..=1)
+        .require_equals(true)
+        .default_missing_value("-")
+    )
   )
 }
 
@@ -3034,6 +3045,8 @@ fn test_parse(flags: &mut Flags, matches: &mut ArgMatches) {
     Vec::new()
   };
 
+  let junit_path = matches.remove_one::<String>("junit");
+
   flags.subcommand = DenoSubcommand::Test(TestFlags {
     no_run,
     doc,
@@ -3046,6 +3059,7 @@ fn test_parse(flags: &mut Flags, matches: &mut ArgMatches) {
     concurrent_jobs,
     trace_ops,
     watch: watch_arg_parse(matches),
+    junit_path,
   });
 }
 
@@ -5910,6 +5924,7 @@ mod tests {
           trace_ops: true,
           coverage_dir: Some("cov".to_string()),
           watch: Default::default(),
+          junit_path: None,
         }),
         unstable: true,
         no_prompt: true,
@@ -5988,6 +6003,7 @@ mod tests {
           trace_ops: false,
           coverage_dir: None,
           watch: Default::default(),
+          junit_path: None,
         }),
         type_check_mode: TypeCheckMode::Local,
         no_prompt: true,
@@ -6020,6 +6036,7 @@ mod tests {
           trace_ops: false,
           coverage_dir: None,
           watch: Default::default(),
+          junit_path: None,
         }),
         type_check_mode: TypeCheckMode::Local,
         no_prompt: true,
@@ -6056,6 +6073,7 @@ mod tests {
           trace_ops: false,
           coverage_dir: None,
           watch: Default::default(),
+          junit_path: None,
         }),
         no_prompt: true,
         type_check_mode: TypeCheckMode::Local,
@@ -6086,6 +6104,7 @@ mod tests {
           trace_ops: false,
           coverage_dir: None,
           watch: Default::default(),
+          junit_path: None,
         }),
         no_prompt: true,
         type_check_mode: TypeCheckMode::Local,
@@ -6117,6 +6136,7 @@ mod tests {
           watch: Some(WatchFlags {
             no_clear_screen: false,
           }),
+          junit_path: None,
         }),
         no_prompt: true,
         type_check_mode: TypeCheckMode::Local,
@@ -6147,6 +6167,7 @@ mod tests {
           watch: Some(WatchFlags {
             no_clear_screen: false,
           }),
+          junit_path: None,
         }),
         no_prompt: true,
         type_check_mode: TypeCheckMode::Local,
@@ -6179,6 +6200,67 @@ mod tests {
           watch: Some(WatchFlags {
             no_clear_screen: true,
           }),
+          junit_path: None,
+        }),
+        type_check_mode: TypeCheckMode::Local,
+        no_prompt: true,
+        ..Flags::default()
+      }
+    );
+  }
+
+  #[test]
+  fn test_junit_default() {
+    let r = flags_from_vec(svec!["deno", "test", "--junit"]);
+    assert_eq!(
+      r.unwrap(),
+      Flags {
+        subcommand: DenoSubcommand::Test(TestFlags {
+          no_run: false,
+          doc: false,
+          fail_fast: None,
+          filter: None,
+          allow_none: false,
+          shuffle: None,
+          files: FileFlags {
+            include: vec![],
+            ignore: vec![],
+          },
+          concurrent_jobs: None,
+          trace_ops: false,
+          coverage_dir: None,
+          watch: Default::default(),
+          junit_path: Some("-".to_string()),
+        }),
+        type_check_mode: TypeCheckMode::Local,
+        no_prompt: true,
+        ..Flags::default()
+      }
+    );
+  }
+
+  #[test]
+  fn test_junit_with_path() {
+    let r = flags_from_vec(svec!["deno", "test", "--junit=junit.xml"]);
+    assert_eq!(
+      r.unwrap(),
+      Flags {
+        subcommand: DenoSubcommand::Test(TestFlags {
+          no_run: false,
+          doc: false,
+          fail_fast: None,
+          filter: None,
+          allow_none: false,
+          shuffle: None,
+          files: FileFlags {
+            include: vec![],
+            ignore: vec![],
+          },
+          concurrent_jobs: None,
+          trace_ops: false,
+          coverage_dir: None,
+          watch: Default::default(),
+          junit_path: Some("junit.xml".to_string()),
         }),
         type_check_mode: TypeCheckMode::Local,
         no_prompt: true,