refactor(core): include_js_files! 'dir' option doesn't change specifiers (#18019)

This commit changes "include_js_files!" macro from "deno_core"
in a way that "dir" option doesn't cause specifiers to be rewritten 
to include it.

Example:
```
include_js_files! {
  dir "js",
  "hello.js",
}
```

The above definition required embedders to use:
`import ... from "internal:<ext_name>/js/hello.js"`. 
But with this change, the "js" directory in which the files are stored
is an implementation detail, which for embedders results in: 
`import ... from "internal:<ext_name>/hello.js"`.

The directory the files are stored in, is an implementation detail and 
in some cases might result in a significant size difference for the 
snapshot. As an example, in "deno_node" extension, we store the 
source code in "polyfills" directory; which resulted in each specifier 
to look like "internal:deno_node/polyfills/<module_name>", but with 
this change it's "internal:deno_node/<module_name>". 

Given that "deno_node" has over 100 files, many of them having 
several import specifiers to the same extension, this change removes
10 characters from each import specifier.

1 files changed, 2 insertions, 2 deletions

diff --git a/ext/node/polyfills/async_hooks.ts b/ext/node/polyfills/async_hooks.ts
index 295f01ec8..5c10e3ee7 100644
--- a/ext/node/polyfills/async_hooks.ts
+++ b/ext/node/polyfills/async_hooks.ts
@@ -4,8 +4,8 @@
 // This implementation is inspired by "workerd" AsyncLocalStorage implementation:
 // https://github.com/cloudflare/workerd/blob/77fd0ed6ddba184414f0216508fc62b06e716cab/src/workerd/api/node/async-hooks.c++#L9
 
-import { validateFunction } from "internal:deno_node/polyfills/internal/validators.mjs";
-import { core } from "internal:deno_node/polyfills/_core.ts";
+import { validateFunction } from "internal:deno_node/internal/validators.mjs";
+import { core } from "internal:deno_node/_core.ts";
 
 function assert(cond: boolean) {
   if (!cond) throw new Error("Assertion failed");