Bump timeout for post-release-push-image-kube-cross

Signed-off-by: Davanum Srinivas <[email protected]>

Author: dims

config/jobs/image-pushing/releng/k8s-staging-build-image.yaml

@@ -70,6 +70,9 @@ postsubmits:
         testgrid-dashboards: sig-release-releng-informing, sig-release-master-informing, sig-release-image-pushes, sig-k8s-infra-gcb
         testgrid-alert-email: [email protected]
       decorate: true
+      decoration_config:
+        timeout: 240m
+        grace_period: 10m
       run_if_changed: '^images\/build\/go-runner\/'
       branches:
         - ^main$