chore(all): auto-regenerate .pb.go files (#883)

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#6545

Changes:

fix: better support for fallback mode
  PiperOrigin-RevId: 468790263
  Source-Link: googleapis/googleapis@873ab45

feat(apigeeregistry): added support for `force` field for API and API version deletion docs: updated proto comments to align with the public documentation
  Clients can now set the `force` field while sending delete request to allow cascade deletion of resources in the registry.

  PiperOrigin-RevId: 468760464
  Source-Link: googleapis/googleapis@b965a25

chore: regenerate API index

  Source-Link: googleapis/googleapis@ed55a83

chore(servicecontrol): remove unused proto imports
  PiperOrigin-RevId: 468735472
  Source-Link: googleapis/googleapis@cfa1b37