chore(all): auto-regenerate .pb.go files (#952)

This is an auto-generated regeneration of the .pb.go files by
cloud.google.com/go/internal/gapicgen. Once this PR is submitted, genbot will
update the corresponding PR to depend on the newer version of go-genproto, and
assign reviewers. Whilst this or any regen PR is open in go-genproto, genbot
will not create any more regeneration PRs. If all regen PRs are closed,
gapicgen will create a new set of regeneration PRs once per night.

If you have been assigned to review this PR, please:

- Ensure that CI is passing. If it's failing, it requires your manual attention.
- Approve and submit this PR if you believe it's ready to ship. That will prompt
genbot to assign reviewers to the google-cloud-go PR.

Corresponding google-cloud-go PR: googleapis/google-cloud-go#7142

Changes:

docs(metastore): Fix formatting for subnetwork field pattern
  PiperOrigin-RevId: 493082091
  Source-Link: googleapis/googleapis@45694d2

docs: fix minor docstring formatting
  PiperOrigin-RevId: 492509862
  Source-Link: googleapis/googleapis@83c3605

chore(deps): Update gapic-generator-java to 2.11.0
  PiperOrigin-RevId: 492463228
  Source-Link: googleapis/googleapis@e365b4c

feat: Introduce an `optional_indices` field to make it possible to conditionally populate a list element in a list literal
  PiperOrigin-RevId: 492445049
  Source-Link: googleapis/googleapis@d139158

chore: regenerate API index

  Source-Link: googleapis/googleapis@0392d22

feat(speech): Added new fields to facilitate debugging * Added new field to Speech response proto, to give more information to indicate whether, or not, Biasing was applied (eg. did Biasing application timed out). * Added request_id to Speech response protos.
  PiperOrigin-RevId: 492276727
  Source-Link: googleapis/googleapis@4c25335