[Feature] Add Apple Silicon / XCFramework support

[hokstuff]

TrustKit is currently only distributed via a .framework file, which is old, limited format and doesn't support running on simulators of Apple Silicon Macs.

By distributing the artifacts as XCFrameworks, it will allow Trustkit to contain both slices of the arm64 architecture (one for iPhones, and one for Apple Silicon simulators). Once implemented, it will support more than a single arm64 slice, which will allow it to be run on simulators of Apple Silicon devices.

[markph0204]

Please consider #304 to resolve this issue.