RFR: 8370851: Mark hotspot and jdk tests incompatible with test thread factory

[Leonid Mesnik]

There are some tests not compatible with with test thread factory. They are marked with corresponding requires tag.

Currently, the only "Virtual" test thread factory exist. It tries to start threads as virtual threads.

The tests that are incompatible with test thread factory are marked with
test.thread.factory == null
and the tests that are rather incompatible with virtual threads are makred
with
test.thread.factory != "Virtual"

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

Commit messages:
 - 8370851: Mark hotspot and jdk tests incompatible with test thread factory

Changes: https://git.openjdk.org/jdk/pull/28030/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28030&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8370851
  Stats: 32 lines in 14 files changed: 17 ins; 1 del; 14 mod
  Patch: https://git.openjdk.org/jdk/pull/28030.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28030/head:pull/28030

PR: https://git.openjdk.org/jdk/pull/28030