chore: update librarian version to v0.42.0

[suztomo]

Update librarian version to v0.42.0.

Note: Running librarian tidy reordered the released_version field under java: across library entries in librarian.yaml to match the struct field declaration order of JavaLibrary in googleapis/librarian (internal/config/language.go).

Included Librarian Updates

• chore(main): release 0.42.0 librarian#7524: chore(main): release 0.42.0
• build(.github/workflows): separate java integration test into standalone job librarian#7489: build(.github/workflows): separate java integration test into standalone job
• chore(main): release 0.41.0 librarian#7473: chore(main): release 0.41.0

[gemini-code-assist]

Note

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