build(deps): bump homebrew/core/protobuf/29 in /protoc-builder/hack (#767)

Bumps homebrew/core/protobuf/29 from 29.4 to 29.5_1.

---
updated-dependencies:
- dependency-name: homebrew/core/protobuf/29
  dependency-version: 29.5_1
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

protoc-builder/hack/Dockerfile.protobuf

@@ -1,3 +1,3 @@
 # This Dockerfile exists to allow Dependabot to watch Homebrew builds of protobuf for triggering updates
 # We don't actually use the content of this image in the repo, as this is a dynamically linked version of protoc
-FROM ghcr.io/homebrew/core/protobuf/29:29.4@sha256:5c4a7e5591b8d71a653810b63d5b91294b5321bf7359abeb8b194e26ab44f36e
+FROM ghcr.io/homebrew/core/protobuf/29:29.5_1@sha256:7d4e4394c981bebfae865a38a69369b435a898e673c1dca633f52a673a8fda8f