[TRACKING ISSUE] Ability to specify multiple partitions in a predicate query (redux)

The tracking issue for the Java side PR.

See https://github.com/hazelcast/hazelcast/pull/21319 for details.

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This is a redux of [PR-18171](https://github.com/hazelcast/hazelcast/pull/18171). I'm continuing on from @ashley-taylor.

I've gone with a slightly different approach of making a backwards compatible change to the existing `PartitionPredicate` interface (instead of making an entirely new interface). This seemed lower risk as existing code with single partition keys will continue to work, while anything new can take advantage of the `getPartitionKeys` method.

Breaking changes (list specific methods/types/messages):
* PartitionPredicateImpl constructor

Checklist:
- [x] Labels (`Team:`, `Type:`, `Source:`, `Module:`) and Milestone set
- [ ] Label `Add to Release Notes` or `Not Release Notes content` set
- [ ] 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

Beginne mit dem verlinkten PR 21319 und seinem referenzierten Vorgänger PR-18171; dieses Tracking-Issue nennt keine Dateien oder Tests. Prüfe, ob die Java-seitige Änderung bereits abgeschlossen ist und ob noch Arbeiten am Python-Client offen sind, bevor du die Aufgabe übernimmst.

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