updated error messaging for auth-api-request.getAccountInfoByFederatedUid()

[remziz4]

The previous error handling for the getAccountInfoByFederatedUid() method was misleading. In scenarios where the providerId was valid, but the uid was missing or invalid, the system would still return a "invalid-provider-id" error code. Now, the appropriate error code will be returned depending on which validation is failing.

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