RFR: 7903676: JMH: Simplify GHA pipelines

[Aleksey Shipilev]

JMH currently runs many jobs with matrix taking the optional profile. This means many jobs are not actually doing any useful work. When those jobs run, we have quite a few warnings: "Error: Path Validation Error: Path(s) specified in the action for caching do(es) not exist, hence no cache is being saved."

We can merge current pipelines a bit to simplify the whole thing.

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Commit messages:
 - Fix

Changes: https://git.openjdk.org/jmh/pull/128/files
 Webrev: https://webrevs.openjdk.org/?repo=jmh&pr=128&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7903676
  Stats: 18 lines in 1 file changed: 0 ins; 2 del; 16 mod
  Patch: https://git.openjdk.org/jmh/pull/128.diff
  Fetch: git fetch https://git.openjdk.org/jmh.git pull/128/head:pull/128

PR: https://git.openjdk.org/jmh/pull/128