NG SDK to RC.1

Updating the NG SDK version of UIKit to the official release candidate.

What's Changed

• Multi Dependencies SwiftPM Fix by @maxxfrazer in #72
• DocC Update on SPI by @maxxfrazer in #73
• API References Update by @maxxfrazer in #74

Full Changelog: 4.0.0-preview.13...4.0.0-rc.1