Remove unnecessary setup-gpg workflow step

Author: olafurpg

.github/workflows/release.yml

@@ -9,7 +9,6 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - uses: olafurpg/setup-scala@v10
-      - uses: olafurpg/setup-gpg@v3
       - run: git fetch --unshallow
       - name: Publish ${{ github.ref }}
         run: sbt ci-release