Add dependabot config to automatically check the version of the actio…

…ns once a month (#823)

.github/dependabot.yml

@@ -0,0 +1,14 @@
+version: 2
+updates:
+  # Enable version updates for github-actions
+  - package-ecosystem: "github-actions"
+    # Look for a `Dockerfile` in the `root` directory
+    directory: "/"
+    # Check for updates once a month
+    schedule:
+      interval: "monthly"
+    labels:
+      - "ci"
+      - "not-breaking"
+      - "B0-silent"
+      - "D2-notlive"