install git for docker change detection

.harness/firebase-deploy.yaml

@@ -22,6 +22,7 @@ spec:
               container: registry-app.inhome.blapointe.com:5001/docker:latest
               shell: sh
               script: |
+                apk add --no-cache git
                 echo build.before = ${{ build.before }}
                 echo build.after = ${{ build.after }}
                 t=registry-app.inhome.blapointe.com:5001/portfolio/resume/builder:latest