Add dependabot config for weekly github-actions updates (#603)

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Co-authored-by: ComradeCow <1058997+ComradeCow@users.noreply.github.com>

Author: Copilot

.github/dependabot.yml

@@ -0,0 +1,6 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"