RFR: 8342074: Fix runtime/Thread/TestAlwaysPreTouchStacks.java to be flagless or accept VM flags

[Afshin Zafari]

`createTestJavaProcessBuilder` is used for creating and running a new Java process that accepts flags.

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Commit messages:
 - 8342074: Fix runtime/Thread/TestAlwaysPreTouchStacks.java to be flagless or accept VM flags

Changes: https://git.openjdk.org/jdk/pull/21945/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21945&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8342074
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/21945.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21945/head:pull/21945

PR: https://git.openjdk.org/jdk/pull/21945