chore(deps): add dependabot config for github actions

Author: leonhazen

.github/dependabot.yml

@@ -0,0 +1,14 @@
+version: 2
+
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "tuesday"
+      time: "09:00"
+      timezone: "Australia/Melbourne"
+    groups:
+      all-actions:
+        patterns:
+          - "*"