Update Dependabot configuration for GitHub Actions schedule (#5)

Author: dwydler

.github/dependabot.yml

@@ -1,6 +1,16 @@
+---
+# 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://docs.github.com/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file
+
 version: 2
 updates:
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
+      # Check for updates to GitHub Actions every week
       interval: "weekly"
+      day: "saturday"
+      timezone: "Europe/Berlin"
+      time: "05:00"