[FR] [gazelle]: support use of glob() for sources in BUILDs

[jbedard]

What is the current behavior?

Each individual source file is listed in srcs

Describe the feature

While globs are less efficient it is sometimes negligible or not worth the large list of files in BUILDs, especially if the BUILD files are still partially manually maintained.

Example WIP: https://github.com/bazelbuild/rules_python/compare/f0rmiga/gazelle-glob-indexing