Updated Renovate config to use renovate-config repo directly

For a while, Renovate recommended using the .github repo to store shared presets. In our case, that setup is mostly just an alias to renovate-config, and it adds indirection and confusion about what our standard source should be.

Going forward, we don't want to use the .github repo for this. Having a dedicated renovate-config repo is more intuitive, so this switches to the direct preset source and standardizes where shared Renovate config comes from.

Author: ErisDS

renovate.json

@@ -1,5 +1,5 @@
 {
   "extends": [
-    "@tryghost:quietJS"
+    "github>TryGhost/renovate-config"
   ]
 }