chore: disable major Go dependency updates in Renovate (#94)

Major Go module version bumps require import path changes throughout the
source code, which Renovate cannot do automatically. Disable these PRs
to avoid noise from incomplete updates.

Author: carole-lavillonniere

renovate.json

@@ -21,7 +21,7 @@
       "matchManagers": ["gomod"],
       "excludePackageNames": ["go"],
       "matchUpdateTypes": ["major"],
-      "groupName": "Go dependencies (major)"
+      "enabled": false
     }
   ]
 }