Fixed typo REVERSED_CLIENT_ID

[kwmt]

https://firebase.google.com/docs/auth/ios/google-signin?hl=en#2_implement_google_sign_in

[googlebot]

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[kwmt]

I signed it!

[googlebot]

CLAs look good, thanks!

[mravn-google]

Thanks for the correction. Can I ask you to also correct a similar mistake in the example app here?

[kwmt]

@mravn-google Sure! I completed.

[mravn-google]

LGTM