jmx-dev RFR: 8326666: Remove the Java Management Extension (JMX) Subject Delegation feature

[Kevin Walls]

The deprecated Subject Delegation feature in JMX will be removed.

This was marked in JDK 21 as deprecated for removal (JDK-8298966).

-------------

Commit messages:
 - JMXConnector to throw UnsupportedOperationException
 - RMIConnectionImpl to throw when RMI calls invoke with delegatedSubject.  Removal of SubjectDelegator class.
 - Use default method.
 - Remove delegationSubject from private class RemoteMBeanServerConnection
 - 8326666: Remove the Java Management Extension (JMX) Subject Delegation feature

Changes: https://git.openjdk.org/jdk/pull/18025/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18025&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8326666
  Stats: 1642 lines in 29 files changed: 18 ins; 1547 del; 77 mod
  Patch: https://git.openjdk.org/jdk/pull/18025.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18025/head:pull/18025

PR: https://git.openjdk.org/jdk/pull/18025