RFR: CODETOOLS-7903471: JMH: Add test for virtual threads executor [v2]

[Sergey Kuksenko]

> Add test for virtual thread executor

Sergey Kuksenko has updated the pull request incrementally with one additional commit since the last revision:

  cleanup

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Changes:
  - all: https://git.openjdk.org/jmh/pull/103/files
  - new: https://git.openjdk.org/jmh/pull/103/files/52aa5d70..ea8df735

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jmh&pr=103&range=01
 - incr: https://webrevs.openjdk.org/?repo=jmh&pr=103&range=00-01

  Stats: 14 lines in 1 file changed: 0 ins; 1 del; 13 mod
  Patch: https://git.openjdk.org/jmh/pull/103.diff
  Fetch: git fetch https://git.openjdk.org/jmh.git pull/103/head:pull/103

PR: https://git.openjdk.org/jmh/pull/103