let dependabot handle github actions updates

Author: bakito

.github/dependabot.yml

@@ -10,4 +10,8 @@ updates:
     schedule:
       interval: "weekly"
     ignore:
-      - dependency-name: "k8s.io/*"
+      - dependency-name: "k8s.io/*"
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"