Add `@scala.annotation.internal.preview` annotation and `-preview` flag. #1591

Job	Run time
Deploy and Test on Mac ARM64 architecture	4m 18s
Deploy and Test on Linux x64 architecture	5m 26s
Deploy and Test on Linux ARM64 architecture	0s
Deploy and Test on Mac x64 architecture	8m 26s
Deploy and Test on Windows x64 architecture	7m 6s
	25m 16s

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