add the needed CODE_PUSH_APK_BUILD_TIME value into gradle build config

[capaj]

without this, you get:

05-23 20:17:27.307  6010  7208 E ReactNative: [CodePush] Exception
05-23 20:17:27.307  6010  7208 E ReactNative: com.microsoft.codepush.react.CodePushUnknownException: Error in getting binary resources modified time
05-23 20:17:27.307  6010  7208 E ReactNative:     at com.microsoft.codepush.react.CodePush.getBinaryResourcesModifiedTime(CodePush.java:207)
05-23 20:17:27.307  6010  7208 E ReactNative:     at com.microsoft.codepush.react.CodePushNativeModule$3.doInBackground(CodePushNativeModule.java:289)
05-23 20:17:27.307  6010  7208 E ReactNative:     at com.microsoft.codepush.react.CodePushNativeModule$3.doInBackground(CodePushNativeModule.java:284)
05-23 20:17:27.307  6010  7208 E ReactNative:     at android.os.AsyncTask$3.call(AsyncTask.java:394)
05-23 20:17:27.307  6010  7208 E ReactNative:     at java.util.concurrent.FutureTask.run(FutureTask.java:266)
05-23 20:17:27.307  6010  7208 E ReactNative:     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
05-23 20:17:27.307  6010  7208 E ReactNative:     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
05-23 20:17:27.307  6010  7208 E ReactNative:     at java.lang.Thread.run(Thread.java:920)
05-23 20:17:27.307  6010  7208 E ReactNative: Caused by: android.content.res.Resources$NotFoundException: String resource ID #0x0
05-23 20:17:27.307  6010  7208 E ReactNative:     at android.content.res.Resources.getText(Resources.java:444)
05-23 20:17:27.307  6010  7208 E ReactNative:     at android.content.res.Resources.getString(Resources.java:537)
05-23 20:17:27.307  6010  7208 E ReactNative:     at com.microsoft.codepush.react.CodePush.getBinaryResourcesModifiedTime(CodePush.java:204)
05-23 20:17:27.307  6010  7208 E ReactNative:     ... 7 more
05-23 20:17:27.308  6010  7202 I ReactNativeJS: [CodePush] An unknown error occurred.
05-23 20:17:27.308  6010  7202 I ReactNativeJS: [CodePush] Error in getting binary resources modified time

[Boztown]

I currently have to do this in two projects so I agree it might be worth noting in the setup docs.

[velimir-jankovic]

This was fixed in https://github.com/microsoft/react-native-code-push/pull/2337