[lldb][test] 2 - Add gmodules test category explicitly where previously done implicitly

[lldb][test] 2 - Add gmodules test category explicitly where previously done implicitly

Since we don't compile with `gmodules` implicitly via
debug-info test replication, we should mark all implicit
`gmodules` tests with the appropriate category so the API
tests get actually run as intended.

Differential Revision: https://reviews.llvm.org/D134574