Add condition to GPG key decoding to handle pull requests

.github/workflows/release.yml

@@ -170,6 +170,7 @@ jobs:
         run: sudo apt update && sudo apt install -y -q gcc-arm-linux-gnueabihf gcc-aarch64-linux-gnu
 
       - name: Decode GPG signing key
+        if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository
         env:
           GPG_RPM_PRIVATE_KEY: ${{ secrets.GPG_RPM_PRIVATE_KEY }}
         run: |