RFR: 8318455: Fix the compiler/sharedstubs/SharedTrampolineTest.java and SharedStubToInterpTest.java

[Evgeny Nikitin]

A continuation of #16258.

Said tests try to control the compilers used via arguments passed to subprocesses' they create. The [JDK-8314838](https://bugs.openjdk.org/browse/JDK-8314838) added support for additional forwarding of the JTReg javaoptions to the subprocesses, but broke the original arguments passing. They are now passed to the enclosing driver and simply ignored by ProcessTools.createTestJvm. As a result, proper compiler may be not chosen on subprocess start, etc. This PR fixes that.

Testing: both tests run in CI, with additional arguments (tests were ignored, as expected) and without (passed).

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Commit messages:
 - 8318455: Fix the compiler/sharedstubs/SharedTrampolineTest.java and SharedStubToInterpTest.java

Changes: https://git.openjdk.org/jdk/pull/16277/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16277&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8318455
  Stats: 8 lines in 3 files changed: 3 ins; 2 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/16277.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16277/head:pull/16277

PR: https://git.openjdk.org/jdk/pull/16277