Fix nightly releases access to Bazel remote cache

Author: p0deje

.github/workflows/nightly.yml

@@ -29,6 +29,7 @@ jobs:
         with:
           workflow: ruby
           key: bazel-ruby-nightly-${{ matrix.gem }}
+          gcs-key: ${{ secrets.GOOGLE_CLOUD_STORAGE_KEY }}
       - uses: ./.github/actions/bazel
         with:
           command: run //rb:${{ matrix.gem }}-bump-nightly-version ${{ inputs.version }}