build: Temporarily turn off renovate automerge

We still have two repositories to merge into frontend-base: frontend-component-footer and frontend-plugin-framework.  If Renovate pushes commits to main while we're trying to pull in hundreds of commits from those repositories, it makes rebasing on top of renovate's commits nearly impossible.

For now, let's just turn off auto-merging of renovate commits until we get these repos in.

renovate.json

@@ -4,7 +4,7 @@
     "config:recommended"
   ],
   "patch": {
-    "automerge": true
+    "automerge": false
   },
   "rebaseStalePrs": true,
   "packageRules": [
@@ -17,7 +17,7 @@
     {
       "matchPackagePatterns": ["@edx", "@openedx"],
       "matchUpdateTypes": ["minor", "patch"],
-      "automerge": true
+      "automerge": false
     }
   ]
 }