RFR: 8319540: GC: Make TestSelectDefaultGC use createTestJavaProcessBuilder

[Leo Korinth]

On Thu, 20 Nov 2025 11:02:35 GMT, Ramkumar Sunderbabu <rsunderbabu at openjdk.org> wrote:

> Make TestSelectDefaultGC forward VM/JAVA_OPTIONS.
> 
> Testing:
> Tiers 1 to 5
> Ran with all flag combinations in CI

I think your test change is good. Another way would have been to use `@require vm.flagless` (in addition to the existing `@require`). I think your change is slightly better as it will test more flag combinations.

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Marked as reviewed by lkorinth (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/28422#pullrequestreview-3511538908