[auth-swift] Restore Recaptcha Enterprise integration

[paulb777]

Fix #13154

Restore the Objective-C implementation for the reflection calls necessary to integrate with the Recaptcha Enterprise weak dependency. The Initialize Recaptcha button in the sample app now succeeds.

Provide a bridge to the Objective-C protocol provided by the optional Recaptcha Enterprise dependency. Once the Recaptcha Enterprise provides a Swift interop protocol, this C and Objective-C code can be converted to Swift. Casting to a Objective-C protocol does not seem possible in Swift. The C API is a workaround for linkage problems with an Objective-C API.

[google-oss-bot]

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:warning:	New public headers were added, did you remember to add them to the umbrella header?

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✅  No API diff detected

Commit: 155d2a2526ae058c225a3bff065cabdc725ce9b7 Last updated: Mon Jul 1 09:39 PDT 2024 View workflow logs & download artifacts

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[paulb777]

@ncooke3 Thanks for the thorough review!

[paulb777]

Going to merge here. I'll address any additional comments in a subsequent PR