[Bug] `monaco-editor-webpack-plugin` resolves `customLanguages` from `path.join(monacoEditorPath, "esm")` when `monacoEditorPath` is supplied

Reproducible in vscode.dev or in VS Code Desktop?

• Not reproducible in vscode.dev or VS Code Desktop

Reproducible in the monaco editor playground?

• Not reproducible in the monaco editor playground

Monaco Editor Playground Link

No response

Monaco Editor Playground Code

No response

Reproduction Steps

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Actual (Problematic) Behavior

No response

Expected Behavior

No response

Additional Context

This is a monaco-editor-webpack-plugin bug, so it doesn't apply to the playground.

This is fairly minor, but if you supply a monacoEditorPath, it's a bit unexpected that customLanguages paths would be resolved from path.join(monacoEditorPath, "esm"). Custom languages aren't going to be "monaco paths," so I wouldn't expect any paths passed in there to need to run through resolveMonacoPath. However, the entry paths get aggregated into languagePaths here: https://github.com/microsoft/monaco-editor/blob/94c055bcbdd49f04a0fa15515e848542a79fb948/webpack-plugin/src/index.ts#L251

Then those are all run through resolveMonacoPath here: https://github.com/microsoft/monaco-editor/blob/94c055bcbdd49f04a0fa15515e848542a79fb948/webpack-plugin/src/index.ts#L312

Then, because monacoEditorPath is passed in, you hit the first condition, causing it to throw an error when trying to resolve the path from path.join(monacoEditorPath, "esm"): https://github.com/microsoft/monaco-editor/blob/94c055bcbdd49f04a0fa15515e848542a79fb948/webpack-plugin/src/index.ts#L25-L27

The same issue happens with the worker paths in getWorkerFilename: https://github.com/microsoft/monaco-editor/blob/94c055bcbdd49f04a0fa15515e848542a79fb948/webpack-plugin/src/index.ts#L49

Start in webpack-plugin/src/index.ts, reading resolveMonacoPath and the code around the reported lines where custom language and worker paths are collected and resolved. Verify the behavior when monacoEditorPath is supplied; done means customLanguages and worker paths are handled without being incorrectly resolved as Monaco paths.