[jdk17u-dev] RFR: 8286873: Improve websocket test execution time

[Goetz Lindenmaier]

I backport this for parity with 17.0.7-oracle.

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Commit messages:
 - Backport d24c84e7687890db88550b05ff9eebe9cae361b2

Changes: https://git.openjdk.org/jdk17u-dev/pull/1110/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1110&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8286873
  Stats: 140 lines in 10 files changed: 68 ins; 39 del; 33 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1110.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev pull/1110/head:pull/1110

PR: https://git.openjdk.org/jdk17u-dev/pull/1110