added dependabot (#4)

This will keep the Github Actions and NPM dependencies up to date

.github/dependabot.yml

@@ -0,0 +1,13 @@
+# Set update schedule for GitHub Actions
+
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      # Check for updates to GitHub Actions every week
+      interval: "weekly"
+  - package-ecosystem: "npm"
+    directory: "/"
+    schedule:
+      interval: "weekly"