Add `@scala.annotation.internal.preview` annotation and `-preview` flag. #57

Job	Run time
Deploy and Test on Linux ARM64 architecture	4m 43s
Deploy and Test on Mac x64 architecture	10m 10s
Deploy and Test on Linux x64 architecture	5m 4s
Deploy and Test on Mac ARM64 architecture	6m 25s
Deploy and Test on Windows x64 architecture	7m 12s
	33m 34s

Provide feedback