build(deps): bump sigstore/cosign-installer from 3.7.0 to 3.8.0

Bumps [sigstore/cosign-installer](https://github.com/sigstore/cosign-installer) from 3.7.0 to 3.8.0.
- [Release notes](https://github.com/sigstore/cosign-installer/releases)
- [Commits](sigstore/cosign-installer@dc72c7d...c56c2d3)

---
updated-dependencies:
- dependency-name: sigstore/cosign-installer
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

.github/workflows/goreleaser.yml

@@ -25,7 +25,7 @@ jobs:
       with:
         go-version: "1.23"
         check-latest: true
-    - uses: sigstore/cosign-installer@dc72c7d5c4d10cd6bcb8cf6e3fd625a9e5e537da # tag=v2.8.1
+    - uses: sigstore/cosign-installer@c56c2d3e59e4281cc41dea2217323ba5694b171e # tag=v2.8.1
     - name: Set up QEMU
       uses: docker/setup-qemu-action@53851d14592bedcffcf25ea515637cff71ef929a # tag=v3.3.0
     - name: Docker login