Support iOS 12

[xalanq]

Why did you upgrade iOS deployment target to 13.0 from 12.1 in this commit #1591 ?

flutter-webrtc/example/ios/Podfile

Line 2 in 5fe7976

platform :ios, '13.0'

[jakobleck]

https://en.wikipedia.org/wiki/IOS_version_history iOS 12 is quite old, not sure you can expect it still being supported...

[xalanq]

https://en.wikipedia.org/wiki/IOS_version_history iOS 12 is quite old, not sure you can expect it still being supported...

I think the 3rd party library should use the minimum supported os version that it could, whatever the version is quite old or not.

[xalanq]

If the lib has not used any new feature of iOS 13.0, it should not declare the minimum iOS deployment target as 13.0.

[cloudwebrtc]

This is because the minimum deployment requirement for libwebrtc to compile the framework dependency on iOS is 13.0