Enable config migration PRs from Renovate (#3296)

correctmost · web-flow · commit 0e8d2c139b41 · 2025-03-23T12:31:36.000+11:00
This will help keep the config file updated with renamed options
and values.
diff --git a/renovate.json b/renovate.json
@@ -4,6 +4,7 @@
     "config:base",
     "helpers:pinGitHubActionDigests"
   ],
+  "configMigration": true,
   "pre-commit": {
     "enabled": true
   },
