chore(tests): workaround to not rely on helpers from KTF

[programmer04]

What this PR does / why we need it:

This PR copies code for helpers waitForServiceLoadBalancerAddress & waitForConnectionOnServicePort from already merged PR Kong/kubernetes-testing-framework#643 in KTF project. This is a temporary solution. The purpose is to have helpers that use EndpointSlices API without upgrading the KTF version. Currently, upgrading is hard due to a dependencies mismatch. If you would like to learn more check issue #3981. It will be reverted when we are able to upgrade KTF.

Which issue this PR fixes:

It's needed to finish #3916

[codecov]

Codecov Report

Patch coverage has no change and project coverage change: +15.4 🎉

Comparison is base (35de761) 58.8% compared to head (2d8ae3d) 74.3%.

Additional details and impacted files

@@           Coverage Diff            @@
##            main   #3980      +/-   ##
========================================
+ Coverage   58.8%   74.3%   +15.4%     
========================================
  Files        142     142              
  Lines      15996   15996              
========================================
+ Hits        9416   11894    +2478     
+ Misses      5950    3355    -2595     
- Partials     630     747     +117     

see 44 files with indirect coverage changes

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[czeslavo]

👍 Makes sense to me to overcome the KTF issue this way.

@programmer04 Have you explicitly removed the team-k8s-maintainers from reviewers of this PR? I cannot see such an event logged in the PR, while the codeowners should be added as reviewers automatically. I ask because I haven't got a notification for this. Maybe it's because of the recent GH's problems with their services 🤔

[programmer04]

@czeslavo good catch! Nope I think it's GH issue, when I marked this as ready for review I got 500, but it became ready for review 😅

[pmalek]

It seems that some of the tests are failing 🤔 I don't believe this could possibly be related and if that's the case we should note down the tests and create issue(s) for them.

[programmer04]

Yeah, I experienced flakiness today. I've created the issue already #3992. But here is something else, it happened for postgres suite too, but after re-run it passed. I'm going to create a dedicated issue for this