[FVR-299] Start inheriting Power Renovate config (#116)

Part of [FVR-299](https://runway.powerhrg.com/backlog_items/FVR-299)

This will ensure Power-standard Renovate config options like tagging
Renovate PRs with the 'dependencies' label, ignoring updates to the
`.github/workflows/stale.yml` file, and other important Renovate config
options are respected in this repository.

Author: c-gerke

renovate.json

@@ -1,6 +1,6 @@
 {
   "extends": [
-    "config:base"
+    "github>powerhome/renovate-config"
   ],
   "ignorePaths": [
     "spec/fixtures"