feat: Add `str.normalize()` #14165

Job	Run time
check-features	9m 48s
check-wasm	6m 42s
integration-test (ubuntu-latest)	1m 48s
test (ubuntu-latest)	3m 43s
integration-test (windows-latest)	5m 59s
test (windows-latest)	9m 36s
	37m 36s

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