v2.22.0

New Libraries

We are happy to announce the following GA libraries. Unless specifically noted,
the APIs in these libraries are stable, and are ready for production use.

• Security Center Management API

Bigtable

• feat: promote EnableServerRetriesOption (#13698)
• feat(bigtable): install mocks library (#13551)

Pub/Sub

• docs(pubsub): add doxygen comment to deprecate handwritten apis (#13585)

Spanner

• feat(spanner): add support for max commit delay (#13562)
• feat: install mocks for spanner, sql, pubsublite (#13548)

Storage

• docs(GCS+gRPC): add contact info (#13688)
• feat(storage): support listing folders as prefixes (#13683)
• feat(storage): support soft-deleted objects (#13644)
• feat(storage): support Bucket soft-delete metadata (#13623)

Common Libraries

• feat: cmake option to skip building mock libraries (#13673)
• feat(generator): support request_id-like fields (#13615)
• docs(common): advertise OAuth2 library (#13614)