[TRACKING ISSUE] Explicitly specify executor for CF calls in the 'client' package [HZ-2004]

[hz-devops-test]

The tracking issue for the Java side PR.

See https://github.com/hazelcast/hazelcast/pull/23532 for details.

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Moving away from using the ForkJoinPool#commonPool for the client package.

Related to https://github.com/hazelcast/hazelcast/issues/18190

Checklist:

• [x] Labels (Team:, Type:, Source:, Module:) and Milestone set
• [x] Label Add to Release Notes or Not Release Notes content set
• [x] Request reviewers if possible
• [ ] Send backports/forwardports if fix needs to be applied to past/future releases
• [ ] New public APIs have @Nonnull/@Nullable annotations
• [ ] New public APIs have @since tags in Javadoc

[srknzl]

Does not apply to Node.js client.