Improve CI job dependency / ordering conditions

.gitea/workflows/CI.yaml

@@ -8,6 +8,7 @@ jobs:
   # work, then we'll do a full bootstrapping build starting from Alpine and installing `gocheckout`
   # first thing.
   build-docker:
+    continue-on-error: true
     container:
       image: gas/ci
       volumes:
@@ -53,6 +54,8 @@ jobs:
         run: docker build -t gas/ci ops/devcontainer
 
   release-test:
+    needs: build-docker-bootstrap
+    if: ${{ needs.build-docker-bootstrap.result == 'success' }}
     container:
       image: gas/ci
       volumes: