RFR: 8333825: GenShen: Revert/Remove ShenandoahMaxEvacLABRatio

[William Kemper]

Clean backport

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Commit messages:
 - Backport 6071b4a9a170b2d91522971a3c9b32bbf44eee3b

Changes: https://git.openjdk.org/shenandoah-jdk21u/pull/55/files
  Webrev: https://webrevs.openjdk.org/?repo=shenandoah-jdk21u&pr=55&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8333825
  Stats: 53 lines in 3 files changed: 7 ins; 36 del; 10 mod
  Patch: https://git.openjdk.org/shenandoah-jdk21u/pull/55.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah-jdk21u.git pull/55/head:pull/55

PR: https://git.openjdk.org/shenandoah-jdk21u/pull/55