[jdk18u] RFR: 8274524: SSLSocket.close() hangs if it is called during the ssl handshake

[Prajwal Kumaraswamy]

This is a clean backport.
The fix has been confirmed by running against internal test suite and JCK SSL tests, where the initial failure was observed in test api/javax_net/ssl/SSLSocket/setUseClientMode.html

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Commit messages:
 - Backport 58dae60da0711c4ae0cb23f8ce2328e051d603b2

Changes: https://git.openjdk.java.net/jdk18u/pull/33/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk18u&pr=33&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274524
  Stats: 151 lines in 2 files changed: 151 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk18u/pull/33.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk18u pull/33/head:pull/33

PR: https://git.openjdk.java.net/jdk18u/pull/33