Fixed test ElasticSearchClientProvider value

[Coduz]

This PR fixes and issue with the test that came out after merge of #3315.
The PR build had test passing but after merge the issue arised even if the #3315 branch was up to date with develop

After a bit of investigation on error:

Error: Scenario: Stop datastore after all scenarios Time elapsed: 1.523 s <<< ERROR!
org.eclipse.kapua.service.datastore.exception.DatastoreInternalError: Cannot instantiate Elasticsearch Client
Caused by: java.lang.ClassCastException: org.eclipse.kapua.service.elasticsearch.client.rest.RestElasticsearchClient cannot be cast to org.eclipse.kapua.service.elasticsearch.client.ElasticsearchClientProvider

I've found a test class that had the wrong value for the datastore.elasticsearch.provider property which was pointing to the Client class instead of the ClientProvider.

Related Issue
None

Description of the solution adopted
Just fixed the wrong parameter

Screenshots
None

Any side note on the changes made
None

[codecov]

Codecov Report

Merging #3332 (00c2fb6) into develop (6278827) will decrease coverage by 12.37%.
The diff coverage is n/a.

❗ Current head 00c2fb6 differs from pull request most recent head 73562ee. Consider uploading reports for the commit 73562ee to get more accurate results

@@              Coverage Diff               @@
##             develop    #3332       +/-   ##
==============================================
- Coverage      47.82%   35.44%   -12.38%     
+ Complexity       867      739      -128     
==============================================
  Files           1516     1516               
  Lines          30463    30463               
  Branches        2528     2528               
==============================================
- Hits           14569    10798     -3771     
- Misses         15161    18799     +3638     
- Partials         733      866      +133     

Impacted Files	Coverage Δ
...rc/main/java/org/eclipse/kapua/KapuaException.java	0.00% <0.00%> (-100.00%)	⬇️
...c/main/java/org/eclipse/kapua/KapuaErrorCodes.java	0.00% <0.00%> (-100.00%)	⬇️
...in/java/org/eclipse/kapua/broker/BrokerDomain.java	0.00% <0.00%> (-100.00%)	⬇️
...ain/java/org/eclipse/kapua/event/ServiceEvent.java	0.00% <0.00%> (-100.00%)	⬇️
...n/java/org/eclipse/kapua/broker/BrokerDomains.java	0.00% <0.00%> (-100.00%)	⬇️
...va/org/eclipse/kapua/commons/util/SystemUtils.java	0.00% <0.00%> (-100.00%)	⬇️
...n/java/org/eclipse/kapua/model/domain/Actions.java	0.00% <0.00%> (-100.00%)	⬇️
.../java/org/eclipse/kapua/message/KapuaPosition.java	0.00% <0.00%> (-100.00%)	⬇️
.../java/org/eclipse/kapua/KapuaRuntimeException.java	0.00% <0.00%> (-100.00%)	⬇️
.../java/org/eclipse/kapua/model/query/SortOrder.java	0.00% <0.00%> (-100.00%)	⬇️
... and 526 more