feat(deps): bump github.com/sigstore/sigstore/pkg/signature/kms/gcp

Bumps [github.com/sigstore/sigstore/pkg/signature/kms/gcp](https://github.com/sigstore/sigstore) from 1.8.9 to 1.8.10.
- [Release notes](https://github.com/sigstore/sigstore/releases)
- [Commits](https://github.com/sigstore/sigstore/compare/v1.8.9...v1.8.10)

---
updated-dependencies:
- dependency-name: github.com/sigstore/sigstore/pkg/signature/kms/gcp
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

go.mod

@@ -22,7 +22,7 @@ require (
 	github.com/sigstore/rekor v1.3.6
 	github.com/sigstore/sigstore v1.8.10
 	github.com/sigstore/sigstore/pkg/signature/kms/aws v1.8.9
-	github.com/sigstore/sigstore/pkg/signature/kms/gcp v1.8.9
+	github.com/sigstore/sigstore/pkg/signature/kms/gcp v1.8.10
 	github.com/stretchr/testify v1.9.0
 	github.com/theupdateframework/go-tuf/v2 v2.0.2
 	google.golang.org/api v0.201.0