[jdk17u-dev] RFR: 8306281: function isWsl() returns false on WSL2

[Martin Doerr]

Backport of [JDK-8306281](https://bugs.openjdk.org/browse/JDK-8306281).

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

Commit messages:
 - Backport 9b0baa10b9140045aa3a49b03e685dcd3ea7c623

Changes: https://git.openjdk.org/jdk17u-dev/pull/1493/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1493&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8306281
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1493.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1493/head:pull/1493

PR: https://git.openjdk.org/jdk17u-dev/pull/1493