RFR: 8325482: Test that distinct seeds produce distinct traces for compiler stress flags [v2]

[Saranya Natarajan]

> The existing test (`compiler/debug/TestStress.java`) verifies that compiler stress options produce consistent traces when using the same seed. However, there is currently no test to ensure that different seeds result in different traces.
> 
> ### Solution
> Added a test case to assess the distinctness of traces generated from different seeds. This fix addresses the fragility concern highlighted in [JDK-8325482](https://bugs.openjdk.org/browse/JDK-8325482) by verifying that traces produced using N (in this case 10) distinct seeds are all not identical.
> 
> ### Changes to `compiler/debug/TestStress.java`
> While investigating this issue, I observed that in `compiler/debug/TestStress.java`, the stress options for macro expansion and macro elimination were not being triggered because there were fewer than 2 macro nodes. Note that the  `shuffle_macro_nodes()` in` compile.cpp` is only meaningful when there are more than two macro nodes. The generated traces for macro expansion and macro elimination in `TestStress.java` were empty. I have proposed changes to address this problem.

Saranya Natarajan has updated the pull request incrementally with two additional commits since the last revision:

 - changing N to 5
 - Adding test for same seed --> same result for N = 10

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/26554/files
  - new: https://git.openjdk.org/jdk/pull/26554/files/513ab6d3..14617e01

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26554&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26554&range=00-01

  Stats: 29 lines in 1 file changed: 16 ins; 1 del; 12 mod
  Patch: https://git.openjdk.org/jdk/pull/26554.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26554/head:pull/26554

PR: https://git.openjdk.org/jdk/pull/26554