FINERACT-2488: Fix duplicate results in /api/v2/clients/search

[rhopman]

The /api/v2/clients/search endpoint returns duplicate entries when a client has multiple identifiers matching the search criteria. When searching by identifier document key, clients with multiple matching identifiers appear multiple times in the result set.

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[rhopman]

I see that the Verify Liquibase Backward Compatibility check failed. I ran it locally, and on my machine it passes (i.e. the service comes up and the health endpoint reports "UP"). I also cannot think of any reason why the change in this PR would cause this check to break. The error does not seem to be related to the change, as far as I can tell.

Can anyone offer some advice here? Is this check usually reliable?