This PR currently breaks iOS extension deployment: We are using an Action Extension which is written in Swift. When deploying it, the build is rejected because of containing a Frameworks/ directory in the .appex bundle.
Inside it, the Swift standard libraries are added (because of this line), which is invalid if your main target already contains Swift - like in our case.
The fix is to check if the main target already includes Swift and set the ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES flag of the extension to NO. We currently hardcoded the value to be unblocked, but eventually a quick PR setting and checking the hasSwiftFiles for the main target.