Update react.gradle (#28776)

Summary:
Running `./gradlew assembleRelease` fails as the path to the CLI contains a new line at the end. We don't run this command in `debug` mode, hence it passed the testing. My bad.

Fixed, checked in both `debug` with `bundleInDebug: true` and `release`.

Fixes #28700

## Changelog

[INTERNAL] [ANDROID] - Fix `React.gradle` to build Android apps in production
Pull Request resolved: #28776

Test Plan: Running `./gradlew assembleRelease` works

Reviewed By: hramos

Differential Revision: D21287789

Pulled By: TheSavior

fbshipit-source-id: dc3ec8eef7a919b072b562d2bd455e2f704bc083

react.gradle

@@ -29,7 +29,7 @@ def detectCliPath(config) {
         return config.cliPath
     }
 
-    def cliPath = ["node", "-e", "console.log(require('react-native/cli').bin);"].execute([], projectDir).text
+    def cliPath = ["node", "-e", "console.log(require('react-native/cli').bin);"].execute([], projectDir).text.trim()
 
     if (cliPath) {
         return cliPath