[jdk17u-dev] RFR: 8293861: G1: Disable preventive GCs by default

[Joshua Cao]

Not a clean backport due to neighboring changes in the same file. Patch is simple and manual fixes are trivial.

As mentioned in the JBS issue, preventive GCs has had issues on JDK 17. We have seen internal applications that are affected by this issue as well.

GHA are full green. Locally run tier1 tests are all green.

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Commit messages:
 - 8293861: G1: Disable preventive GCs by default

Changes: https://git.openjdk.org/jdk17u-dev/pull/1758/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1758&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8293861
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1758.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1758/head:pull/1758

PR: https://git.openjdk.org/jdk17u-dev/pull/1758