[TRIVIAL] Skip test_ensure_on_messsage_is_not_none test for older clients

[yuce]

Recently we added a check for the on_message parameter in the Topic.add_listener message.
Since that check doesn't exist in the released versions of the client, the corresponding test fails for them in the Client compatibility test suite:
https://github.com/hazelcast/client-compatibility-suites/actions/runs/25483639833/job/74776163020

This PR updates the test to skip it for older versions of the client.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.42%. Comparing base (7f69a2d) to head (a0f7aea).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #810   +/-   ##
=======================================
  Coverage   94.41%   94.42%           
=======================================
  Files         401      401           
  Lines       26125    26125           
=======================================
+ Hits        24666    24668    +2     
+ Misses       1459     1457    -2     

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