[MM-37772] Idiomatic naming (URL, URI, API) (#18128)

* s/Url/URL/g & s/Uri/URI/g

* s/Api/API/g

api4/websocket.go

@@ -20,7 +20,7 @@ const (
 
 func (api *API) InitWebSocket() {
 	// Optionally supports a trailing slash
-	api.BaseRoutes.ApiRoot.Handle("/{websocket:websocket(?:\\/)?}", api.ApiHandlerTrustRequester(connectWebSocket)).Methods("GET")
+	api.BaseRoutes.APIRoot.Handle("/{websocket:websocket(?:\\/)?}", api.APIHandlerTrustRequester(connectWebSocket)).Methods("GET")
 }
 
 func connectWebSocket(c *Context, w http.ResponseWriter, r *http.Request) {