Description

Any error thrown by RemoteConfig.fetch that doesn't have the code fetchFailedThrottled is "swallowed" because we're only returning the string "Unable to fetch remote config". This PR replaces the generic message with the message returned from the native side in order to improve debuggability (if this word exists 😅 ).

Related Issues

I couldn't find one related to this specific problem.

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
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