RFR: 8298868: Update EngineCloseOnAlert.java for changes to TLS implementation

[Matthew Donovan]

Refactored the code a little bit and updated the test for changes to the TLS state machine.

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Commit messages:
 - 8298868: Update EngineCloseOnAlert.java for changes to TLS implementation

Changes: https://git.openjdk.org/jdk/pull/11903/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11903&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8298868
  Stats: 57 lines in 2 files changed: 16 ins; 9 del; 32 mod
  Patch: https://git.openjdk.org/jdk/pull/11903.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11903/head:pull/11903

PR: https://git.openjdk.org/jdk/pull/11903