ci(package): login to registry

.github/workflows/package-pr.yaml

@@ -18,6 +18,13 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v2
       
+      - name: Login to GitHub registry
+        uses: docker/login-action@v1
+        with:
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+          registry: docker.pkg.github.com
+          
       - name: Build Packages
         run: |
           docker run -v $(pwd)'/repo:/piston/repo' -v $(pwd)'/packages:/piston/packages' docker.pkg.github.com/engineer-man/piston/repo-builder $(git diff-tree --no-commit-id --name-only -r ${{ github.sha }} | awk -F/ '{ print $2 "-" $3 }' | sort -u) --no-server