I18n: Add locale to user preference (#49425)

* Add __debug_bin file to gitignore

* Add locale user preference

* undo defaulting to existing JSONData in preferences save

.gitignore

@@ -99,6 +99,7 @@ debug.test
 /packaging/**/*.deb
 /packaging/**/*.tar.gz
 /packaging/**/*.tar.gz.sha256
+pkg/cmd/grafana-server/__debug_bin
 
 # Ignore OSX indexing
 .DS_Store
@@ -165,4 +166,3 @@ public/locales/_build/
 public/locales/**/*.js
 
 deployment_tools_config.json
-