FIX - Removed useless elasticsearch dependencies that was linked to the old embedded elasticSearch

[Agnul97]

Brief description of the PR. In this PR I wanted to remove some dependencies that we have in the code with elasticSearch artifacts that we no longer require. Some of them were used by an old "embedded datastore/es instance" used in the tests, something that's been replaced by a ES container now. In this past PR https://github.com/eclipse/kapua/pull/3500 you can see some past attempts to remove references to this embedded datastore stuff but I suppose something was left in the code, here cleaned.

I still wonder why there were such a lot of dependencies to different ElastiSearch clients. I left the only 2 that we now use, namely the rest-client and the high-level-rest-client.

I also cleaned a bit the documentation on the tests section, containing obsolete information or in contrast with more recent info on other parts of the doc. I finally removed completely the qa/common/src/main/java/org/eclipse/kapua/qa/common/utils/EmbeddedDatastore.java class, not being used anywhere an no more containing useful code in it

To verify that these changes were harmless I made a bit of manual testing locally (for example, tried to push some message to a local deployment and fetch them via console or rest) and I verified that CI was passing

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 16.67%. Comparing base (9506c48) to head (e1a2ca8). Report is 2 commits behind head on develop.

Additional details and impacted files

[](https://app.codecov.io/gh/eclipse/kapua/pull/4040?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=eclipse) ```diff @@ Coverage Diff @@ ## develop #4040 +/- ## ========================================== Coverage 16.67% 16.67% Complexity 22 22 ========================================== Files 2009 2009 Lines 52223 52223 Branches 4437 4437 ========================================== Hits 8706 8706 Misses 43113 43113 Partials 404 404 ```