perf(syntax): optimize `is_identifier_name` #16082

Job	Run time
Build Linter Benchmark	5m 23s
Benchmark (lexer)	1m 20s
Benchmark (parser)	1m 35s
Benchmark (transformer)	6m 7s
Benchmark (isolated_declarations)	1m 48s
Benchmark (semantic)	2m 9s
Benchmark (minifier)	2m 17s
Benchmark (codegen)	2m 9s
Benchmark (sourcemap)	2m 0s
Benchmark linter (0)	1m 45s
Benchmark linter (1)	1m 26s
Upload benchmarks	20s
	28m 19s

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