chore: enhance GitHub Actions workflow with max parallel jobs and registry specification

Author: incubator4

.github/workflows/build.yaml

@@ -62,6 +62,7 @@ jobs:
       - stack
     strategy:
       fail-fast: false
+      max-parallel: 3
       matrix:
         target: ${{ fromJson(needs.prepare.outputs.targets) }}
         registry:
@@ -108,6 +109,7 @@ jobs:
       - name: Login to ghcr
         uses: docker/login-action@v2
         with:
+          registry: ghcr.io
           username: ${{ github.actor }}
           password: ${{ github.token }}