Run image building in parallel with tox tests (#371)

Co-authored-by: Bradley A. Thornton <[email protected]>

Author: ssbarnea

.github/workflows/tox.yml

@@ -25,6 +25,8 @@ jobs:
   build-image:
     runs-on: ${{ matrix.builder }}
     name: ${{ matrix.name }}
+    # commented to speedup execution
+    # needs: tox
     services:
       registry:
         image: registry:2
@@ -66,7 +68,9 @@ jobs:
   publish-image:
     environment: release # approval
     runs-on: ubuntu-latest
-    needs: build-image
+    needs:
+      - build-image
+      - tox
     if: github.event_name == 'release' && github.event.action == 'published'
     steps:
       - name: Check out repository