fix: fix codepush.gradle trying to access non-existent directories

[AmyrAhmady]

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This PR fixes common android issue when there's no directory such as android/app/build/generated/res/react/release, either release directory or its parent react There have been multiple issues pointing to this but for some reason no one created a PR for it

this workaround or fix is taken from this comment: https://github.com/microsoft/react-native-code-push/issues/1578#issuecomment-503993512

Some of the related issues:

#1977 #1578 #1866 #1812 #1977