[7.1.0] Emit labels in display form in Java rules (#21395)

Buildozer fixes for Java strict deps violations referring to external
repositories now contain labels in display form, which avoid canonical
repository names that should never be added to BUILD files and aren't
understood by `buildozer`.

The Starlark actions can use `Label.to_display_form()`. Java compilation
actions, which are still implemented in Java, can't access the main
repository mapping via `BazelModuleContext` and instead retrieve it from
a new field on `AnalysisEnvironment`.

Closes #21180.

Commit
https://github.com/bazelbuild/bazel/commit/b11fa7a7c7fdb37012c7a442b16f6fdcf90b9177



PiperOrigin-RevId: 607803030
Change-Id: I0cdccabfde0217c9201cef9ca9d260b0c8ca27cd

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Co-authored-by: Fabian Meumertzheim <fabian@meumertzhe.im>
Co-authored-by: hvadehra <hvd@google.com>