RFR: 8356658: java/foreign/TestBufferStackStress2.java failed again with junit action timed out [v2]

[Per Minborg]

> This PR proposes to add a safety net around closing the executor. Apparently, in some rare configuration, the VT is not run/notified correctly.
> 
> Not completing the test for such a configuration is unlikely to mask potential issues that this test is supposed to reveal.

Per Minborg has updated the pull request incrementally with one additional commit since the last revision:

  Add shutdown

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/25177/files
  - new: https://git.openjdk.org/jdk/pull/25177/files/3547359f..c4f50471

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25177&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25177&range=00-01

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/25177.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25177/head:pull/25177

PR: https://git.openjdk.org/jdk/pull/25177