[JENKINS-72975] Permit java.util.regex.MatchResult.group(String)

[ckullabosch]

See JENKINS-72975.

Testing done

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[dwnusbaum]

Please add all of the other new name-related methods added to MatchResult in Java 20 at the same time. Also, you'll need to add all of them to this set for the tests to pass, since we still support Java 17 and use it in one branch of the CI builds:

script-security-plugin/src/test/java/org/jenkinsci/plugins/scriptsecurity/sandbox/whitelists/StaticWhitelistTest.java

Line 116 in 1399a91

private static final Set<Signature> KNOWN_GOOD_SIGNATURES = new HashSet<>(Arrays.asList(