RFR: 8329493: Parallel: Remove unused ParallelArguments::heap_max_size_bytes

[Albert Mingkun Yang]

Trivial removing dead code.

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Commit messages:
 - trivial

Changes: https://git.openjdk.org/jdk/pull/18575/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18575&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8329493
  Stats: 5 lines in 2 files changed: 0 ins; 5 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/18575.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18575/head:pull/18575

PR: https://git.openjdk.org/jdk/pull/18575