[Github] Revert accidental changes to dependabot config

f3524e9aebbfabed0c60d0087b39ce14d8f778da accidentally touched the
dependabot config. This patch reverts that change.

.github/dependabot.yml

@@ -1,12 +1,18 @@
-# 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 more information:
-# https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
-# https://containers.dev/guide/dependabot
-
 version: 2
 updates:
- - package-ecosystem: "devcontainers"
-   directory: "/"
-   schedule:
-     interval: weekly
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "monthly"
+    groups:
+      github-actions:
+        patterns:
+          - "*"
+  - package-ecosystem: "pip"
+    directory: "/llvm/docs"
+    schedule:
+      interval: "monthly"
+    groups:
+      llvm-docs-requirements:
+        patterns:
+          - "*"