FIX : Return YES if the SSO login isMobileSSOSuccess

[leverdeterre]

Problem

I was not able to properly finalize a login with a Twitter account using Firebase. The Twitter login is actually impossible to enable with the FirebaseUI auth providers.
I noticed an error in your management of OpenUrl in the application delegate

Solution

Say YES when TwitterKit is challenged to open an URL and the SSO is a success. TwitterKit has done the job!

Result

Avoid a crash on the providers loop on the Firebase UI SDK because the SDK will try to find a provider to handle the asked openUrl and your SDK has complete the job 👍

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[ducnv2910]

Please merge it soon. because it doesn't work on swift 4.2

[NathanWalker]

Hi @leverdeterre would you mind sharing how you built this locally? Having trouble building directly from your repo.