refactor(minifier): make `Prepass` `Copy` #9385

Job	Run time
Build Linter Benchmark	2m 42s
Benchmark (lexer)	1m 17s
Benchmark (parser)	1m 18s
Benchmark (transformer)	2m 9s
Benchmark (minifier)	1m 33s
Benchmark (codegen_sourcemap)	1m 35s
Benchmark (sourcemap)	1m 35s
Benchmark linter (0)	1m 46s
Benchmark linter (1)	1m 16s
Upload benchmarks	19s
	15m 30s

Provide feedback