[jdk21u-dev] RFR: 8338281: jshell does not run shutdown hooks

[Satyen Subramaniam]

Backporting JDK-8338281: jshell does not run shutdown hooks. Adjusts logic to now exit the remote agent when receiving the CLOSE event and delays the JShell's close for a moment for the remote process to finish. Ran GHA Sanity Checks, local Tier 1 and 2, and adjusted test. Patch is clean.

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Commit messages:
 - Backport 8c8b5801fd9d28a71edf3bd8d1fae857817e27de

Changes: https://git.openjdk.org/jdk21u-dev/pull/1813/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1813&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8338281
  Stats: 74 lines in 3 files changed: 72 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1813.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1813/head:pull/1813

PR: https://git.openjdk.org/jdk21u-dev/pull/1813