npd: Push images for tags and release branches

Author: hakman

config/jobs/image-pushing/k8s-staging-node-problem-detector.yaml

@@ -9,6 +9,10 @@ postsubmits:
       decorate: true
       branches:
         - ^master$
+        - ^release-.*
+        # Build (root) tags also
+        # this is a regex for semver, from https://semver.org/#is-there-a-suggested-regular-expression-regex-to-check-a-semver-string
+        - ^v(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$
       spec:
         serviceAccountName: gcb-builder
         containers: