[FIX] Skip push on fork PRs

Author: josep-tecnativa

.github/workflows/ci.yaml

@@ -68,14 +68,14 @@ jobs:
         run: docker tag ${{ env.DOCKER_REPO }}:${{ matrix.pg_version }}-alpine ${{ env.DOCKER_REPO }}:${{ env.DOCKER_TAG }}
       # Push
       - name: Push Docker Image to Docker Hub
-        if: github.repository == 'Tecnativa/docker-postgres-autoconf' && (env.IS_PR || github.ref == 'refs/heads/master')
+        if: github.repository == 'Tecnativa/docker-postgres-autoconf' && (github.ref == 'refs/heads/master' || (github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository'))
         env:
           REGISTRY_HOST: docker.io
           REGISTRY_TOKEN: ${{ secrets.DOCKERHUB_TOKEN }}
           REGISTRY_USERNAME: ${{ secrets.DOCKERHUB_LOGIN }}
         run: ./hooks/push
       - name: Push Docker Image to GitHub Registry
-        if: github.repository == 'Tecnativa/docker-postgres-autoconf' && (env.IS_PR || github.ref == 'refs/heads/master')
+        if: github.repository == 'Tecnativa/docker-postgres-autoconf' && (github.ref == 'refs/heads/master' || (github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository'))
         env:
           REGISTRY_HOST: ghcr.io
           REGISTRY_TOKEN: ${{ secrets.BOT_TOKEN }}