Update dependabot.yml

Signed-off-by: Marcel Klehr <mklehr@gmx.net>

Author: marcelklehr

.github/dependabot.yml

@@ -16,3 +16,11 @@ updates:
     time: "03:00"
     timezone: Europe/Paris
   open-pull-requests-limit: 10
+- package-ecosystem: "github-actions"
+  directory: "/"
+  schedule:
+    interval: weekly
+    day: saturday
+    time: "03:00"
+    timezone: Europe/Paris
+  open-pull-requests-limit: 10