feat: Add utility class migration script

What does this MR do?

feat: Add utility class migration script

This adds a migration script for legacy utilities to tailwind utilities.

This was extracted from: gitlab!154442 (merged)

The idea is simple:

1. We give a list of files via stdin or iterate over all source files in the current directory or in a given list of directories.
2. We replace legacy utility class names with their tailwind equivalents (list maintained bin/lib/tailwind_equivalents.js). Note, not all legacy utils are mapped, but just the ones currently in use in the GitLab project and other important projects.
3. You test that the changes have the expected results. Migration strategy for larger projects might be folder by folder or route by route.

Screenshots or screen recordings

N/A

Integration merge requests

Not needed

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• Status Page: mr_url

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