[jdk22u] RFR: 8331142: Add test for number of loader threads in BasicDirectoryModel [v2]

[Alexey Ivanov]

> Provides a regression test for [JDK-8325179](https://bugs.openjdk.org/browse/JDK-8325179): _Race in BasicDirectoryModel.validateFileCache_ which is backported to 22u.

Alexey Ivanov has updated the pull request incrementally with one additional commit since the last revision:

  8331495: Limit BasicDirectoryModel/LoaderThreadCount.java to Windows only
  
  Reviewed-by: prr

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Changes:
  - all: https://git.openjdk.org/jdk22u/pull/175/files
  - new: https://git.openjdk.org/jdk22u/pull/175/files/b5972e32..cae9ec53

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk22u&pr=175&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk22u&pr=175&range=00-01

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk22u/pull/175.diff
  Fetch: git fetch https://git.openjdk.org/jdk22u.git pull/175/head:pull/175

PR: https://git.openjdk.org/jdk22u/pull/175