Correct deintegrate command syntax in documentation (#5207)

Author: retyui

website/blog/2026-08-11-react-native-0.87.mdx

@@ -137,7 +137,7 @@ To try it in an existing/new app:
 ```sh
 cd ios
 # deintegrate will remove CocoaPods from your project
-npx react-native spm -- deintegrate
+npx react-native spm --deintegrate
 ```
 
 The command injects Swift package references into your existing `.xcodeproj` instead of replacing the project. Your signing, capabilities, and build phases stay untouched. `npx react-native spm deinit` reverses the change exactly.