Create a NonCacheRewriter and export cacheRewrittenSourceMap

[uurien]

What does this PR do?

Create a NonCacheRewriter class and export cacheRewrittenSourceMap method.

Motivation

Use this in independent thread to rewrite esm files without loading the cache in this thread, and update the cache in the main thread using exported method.

Additional Notes

Describe how to test your changes

Checklist

• The CHANGELOG.md has been updated
• Unit tests have been updated and pass
• If known, an appropriate milestone has been selected

[iunanua]

Another option could be to continue with a single Rewriter class add a doNotCache parameter to rewrite(code: string, file: string, doNotCache: bool): Result method and skip calling cacheRewrittenSourceMap() when doNotCache: true

But thinking in ESM, I guess it is more elegant to have Rewriter and NonCacheRewriter different classes