RFR: 8328638: Fallback option for POST-only OCSP requests

[Aleksey Shipilev]

See the rationale/discussion in the bug. This patch introduces the option that allows to restore pre-[JDK-8179503](https://bugs.openjdk.org/browse/JDK-8179503) behavior. The default behavior does not change.

Additional testing:
 - [x] `jdk_security` passes (includes new test config)

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Commit messages:
 - Fix

Changes: https://git.openjdk.org/jdk/pull/18408/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18408&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8328638
  Stats: 36 lines in 2 files changed: 32 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/18408.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18408/head:pull/18408

PR: https://git.openjdk.org/jdk/pull/18408