[ROCDOC-593] Update Read the Docs documentation requirements

Change-Id: I48350a42a50f0e85d9f074295e27c20b4b66cdb4

.github/dependabot.yml

@@ -9,11 +9,10 @@ updates:
     directory: "/docs/sphinx" # Location of package manifests
     open-pull-requests-limit: 10
     schedule:
-      interval: "monthly"
-    target-branch: "master"
+      interval: "weekly"
+    target-branch: "develop"
     labels:
       - "documentation"
       - "dependencies"
-      - "ci:docs-only"
     reviewers:
       - "samjwu"