RFR: 8249825: Tests sun/security/ssl/SSLSocketImpl/SetClientMode.java and NonAutoClose.java marked with @ignore

[Fernando Guallini]

The following tests are marked with @ignore (not running):

- sun/security/ssl/SSLSocketImpl/SetClientMode.java: it checks that setting the clientMode after the handshake has begun is not permitted, but this was failing intermittently due to a race condition, it was possible that SetClientMode was called before the client socket was updated with handshake isNegotiated = true. The fix is to introduce a latch to sync between client and main threads. Included additional refactoring to ensure test stability.

- sun/security/ssl/SSLSocketImpl/NonAutoClose.java: This test should only run in TLS <= 1.2, as TLSv1.3 changes the behaviour of close_notify. Included additional refactoring to ensure test stability.

Executed both tests 10K times, no test flakiness found

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

Commit messages:
 - Merge branch 'master' into 8249825
 - SetClientMode minor cleanup
 - NonAutoClose.java and SetClientMode.java passing
 - removed @ignore from NonAutoClose and SetClientMode

Changes: https://git.openjdk.org/jdk/pull/23898/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23898&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8249825
  Stats: 354 lines in 2 files changed: 30 ins; 179 del; 145 mod
  Patch: https://git.openjdk.org/jdk/pull/23898.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23898/head:pull/23898

PR: https://git.openjdk.org/jdk/pull/23898