RFR: 8317538: RSA have scalability issue for high vCPU numbers

[Ben Perez]

Modified `getService` method to prevent caching of `ServiceKey`, which was negatively impacting multithreaded performance

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Commit messages:
 - changed ServiceKey initialization to prevent caching

Changes: https://git.openjdk.org/jdk/pull/16403/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16403&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8317538
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/16403.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16403/head:pull/16403

PR: https://git.openjdk.org/jdk/pull/16403