docs(expo-router): use more descriptive function

Uses a more descriptive function if the app is running in Expo Go instead of the comment.

Author: moritzlang

docs/platforms/react-native/tracing/instrumentation/expo-router.mdx

@@ -13,11 +13,11 @@ The code snippet below shows how to initialize the instrumentation.
 ```javascript {6-8, 15-16, 20-25} {filename: app/_layout.tsx}
 import React from 'react';
 import { Slot, useNavigationContainerRef } from 'expo-router';
-import Constants, { ExecutionEnvironment } from 'expo-constants';
+import { isRunningInExpoGo } from "expo"
 import * as Sentry from '@sentry/react-native';
 
 const navigationIntegration = Sentry.reactNavigationIntegration({
-  enableTimeToInitialDisplay: Constants.executionEnvironment === ExecutionEnvironment.StoreClient, // Only in native builds, not in Expo Go.
+  enableTimeToInitialDisplay: !isRunningInExpoGo(),
 });
 
 Sentry.init({
@@ -26,7 +26,7 @@ Sentry.init({
   // We recommend adjusting this value in production.
   tracesSampleRate: 1.0,
   integrations: [navigationIntegration],
-  enableNativeFramesTracking: Constants.executionEnvironment === ExecutionEnvironment.StoreClient, // Only in native builds, not in Expo Go.
+  enableNativeFramesTracking: !isRunningInExpoGo(),
 });
 
 function RootLayout() {