RFR: 8352617: IR framework test TestCompileCommandFileWriter.java runs TestCompilePhaseCollector instead of itself

[Marc Chevalier]

Simply changing the path in `@run` was not enough (see JBS for details). And actually, the test wasn't doing anything before trying to open an output file to check the result. From various hints, I completed the test: I hope it was the intent!

I think @chhagedorn's eye would be the most relevant.

Thanks,
Marc

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Commit messages:
 - Make TestCompileCommandFileWriter run itself

Changes: https://git.openjdk.org/jdk/pull/24240/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24240&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8352617
  Stats: 10 lines in 1 file changed: 2 ins; 0 del; 8 mod
  Patch: https://git.openjdk.org/jdk/pull/24240.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24240/head:pull/24240

PR: https://git.openjdk.org/jdk/pull/24240