[TRACKING ISSUE] Added support for Map merge operation #14913 [API-1601]

The tracking issue for the Java side PR.

Added support for Map merge operation #14913

See hazelcast/hazelcast#17419 for details.

---

[puzpuzpuz]

Marked this one with low priority as it assumes that the user has to deal with Java code.

[github-actions]

Internal Jira issue: API-1601