Repository: vercel/next.js
Pull request: fix(turbopack): webpack-loaders failed to resolve relative path

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fixed: #82106 

The error was cause by the follow reason, when pass:

```ts
const nextConfig: NextConfig = {
  /* config options here */
  turbopack: {
    rules: {
      '*.txt': {
        loaders: ['./test-file-loader.js'],
        as: '*.js',
      },
    }
  }
};
```

and the project directory as follows:

```bash
src
 |_ app
      |_ index.tsx
      |_ text.txt
```

The loader will deal the `text.txt` under `src/app`, then the loader will resolve path like:

```ts
require.resolve('./test-file-loader.js', paths: ['/Users/next-app/src/app'])
```

Because the resource dir the `dirname(resoucePath)`, and the resourcePath is `/Users/next-app/src/app/text.txt`, this will never resolve the right loader path here.

So I just add a more `path` param(which is `contextDir`) for the require.resolve function, it will help the loader to find the right path here.

Changed files:
filename: test/e2e/app-dir/webpack-loader-binary/next.config.js
patch: @@ -5,7 +5,7 @@ const nextConfig = {
   turbopack: {
     rules: {
       '*.txt': {
-        loaders: [require.resolve('./test-file-loader.js')],
+        loaders: ['./test-file-loader.js'],
         as: '*.js',
       },
       '*.mp4': {
@@ -17,7 +17,7 @@ const nextConfig = {
   webpack(config) {
     config.module.rules.push({
       test: /\.txt/,
-      use: require.resolve('./test-file-loader.js'),
+      use: './test-file-loader.js',
     })
     config.module.rules.push({
       test: /\.mp4/,

filename: turbopack/crates/turbopack-node/js/src/transforms/webpack-loaders.ts
patch: @@ -428,7 +428,7 @@ const transform = (
 
         loaders: loadersWithOptions.map((loader) => ({
           loader: __turbopack_external_require__.resolve(loader.loader, {
-            paths: [resourceDir],
+            paths: [contextDir, resourceDir],
           }),
           options: loader.options,
         })),