[jdk21] RFR: 8311867: StructuredTaskScope.shutdown does not interrupt newly started threads

[Alan Bateman]

Clean backport of https://git.openjdk.org/jdk/pull/14833

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Commit messages:
 - Backport 92a04e201e68aa4d682053cef4b36180ec5620f5

Changes: https://git.openjdk.org/jdk21/pull/123/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21&pr=123&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8311867
  Stats: 99 lines in 3 files changed: 95 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk21/pull/123.diff
  Fetch: git fetch https://git.openjdk.org/jdk21.git pull/123/head:pull/123

PR: https://git.openjdk.org/jdk21/pull/123