configure dependabot

Author: keewis

.github/dependabot.yml

@@ -0,0 +1,11 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      # Check for updates once a week
+      interval: "weekly"
+    groups:
+      actions:
+        patterns:
+          - "*"