feat(all): auto-regenerate .pb.go files (#514)

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#3539

Changes:

fix: generated package names for C#, Ruby, and PHP docs: minor cleanup, formatting and edits
  PiperOrigin-RevId: 351455519
  Source-Link: googleapis/googleapis@b71a6e5

chore(bigquery/storage): use name google.cloud.bigquery_storage namespace to avoid conflicts with google.cloud.bigquery
  PiperOrigin-RevId: 351218127
  Source-Link: googleapis/googleapis@c8bfd32

fix: generated package names for C#, Ruby, and PHP
  PiperOrigin-RevId: 351190966
  Source-Link: googleapis/googleapis@38cb5ce