Explicitly associate files as JSONC (#33410)

Fixes an issue when the zed repo was checked out to folder other than
`zed` (e.g. `zed2`) files were incorrectly identified as JSON instead of
JSONC.

Release Notes:

- N/A

.zed/settings.json

@@ -40,6 +40,7 @@
   },
   "file_types": {
     "Dockerfile": ["Dockerfile*[!dockerignore]"],
+    "JSONC": ["assets/**/*.json", "renovate.json"],
     "Git Ignore": ["dockerignore"]
   },
   "hard_tabs": false,