Add GitHub Actions to Dependabot config (#1402)

Author: ddzz

.github/dependabot.yml

@@ -1,12 +1,14 @@
-# To get started with Dependabot version updates, you'll need to specify which
-# package ecosystems to update and where the package manifests are located.
-# Please see the documentation for all configuration options:
 # https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
 
 version: 2
 updates:
-  - package-ecosystem: "npm" # See documentation for possible values
-    directory: "/" # Location of package manifests
+  - package-ecosystem: 'npm'
+    directory: '/'
     schedule:
-      interval: "weekly"
+      interval: 'weekly'
     open-pull-requests-limit: 10
+
+  - package-ecosystem: 'github-actions'
+    directory: '/'
+    schedule:
+      interval: 'weekly'