[local_auth] Fix iOS app crash issue: alerts should be alled in the m…

[callbiruk]

Fix an issue raised in Xcode:
(NSException *) exception = 0x0000000280f86df0 name: "NSInternalInconsistencyException" - reason: "Modifications to the layout engine must not be performed from a background thread after it has been accessed from the main thread."

Description

This PR resolves an issue for a complete app crash when the biometric lockout happens in the app. The alert throws an error claiming the UI modification should happen in the main thread instead of the background process. Therefore, I run the function in the main thread and wrap it on try catch block for any failure.

Related Issues

None

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[MichaelPretorius]

@callbiruk are you planning on updating your PR so it can pass checks and be merged?

[callbiruk]

@MichaelPretorius CHANGELOG.md

[ttmdung203]

@callbiruk are you planning on updating your PR so it can pass checks and be merged?

Yes, I've the same question. Thanks @callbiruk for your contribution. I'm looking forward to seeing the this update too.

[stuartmorgan-g]

Thanks for the contribution! This is obsoleted by #3778 (which fixed the underlying threading issue rather than just this specific symptom), so closing.