Bump sigstore-protobuf-specs from 0.3.2 to 0.3.5

Bumps [sigstore-protobuf-specs](https://github.com/sigstore/protobuf-specs) from 0.3.2 to 0.3.5.
- [Release notes](https://github.com/sigstore/protobuf-specs/releases)
- [Changelog](https://github.com/sigstore/protobuf-specs/blob/main/CHANGELOG.md)
- [Commits](sigstore/protobuf-specs@v0.3.2...release/rust/v0.3.5)

---
updated-dependencies:
- dependency-name: sigstore-protobuf-specs
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

requirements.txt

@@ -2,4 +2,4 @@ pytest==8.3.4
 pytest-subtests==0.14.1
 requests==2.32.3
 cryptography==44.0.0
-sigstore-protobuf-specs==0.3.2
+sigstore-protobuf-specs==0.3.5