[GR-61457] Warn about unused language allow list entries in language permissions tool. #21044

Job	Run time
/substratevm on Windows	8m 2s
/compiler style,fullbuild,test JDKlatest	30m 24s
/compiler build,bootstraplite JDKlatest	4m 21s
/espresso style,fullbuild JDK21	13m 43s
/substratevm style,fullbuild JDKlatest	11m 53s
/substratevm build,helloworld,native_unittests JDKlatest	20m 26s
/substratevm build,debuginfotest JDKlatest	22m 1s
/substratevm hellomodule JDKlatest	4m 50s
/sulong style,fullbuild,sulongBasic JDK21	20m 20s
/truffle JDK21	35m 21s
/vm build,sulong JDKlatest	26m 28s
/vm build JDKlatest	15m 39s
	3h 33m 28s

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