replace methods of the CRTRestClient with the cached client

[MatousJobanek]

This is a follow-up of #461

It replaces the methods of the custom CRTRestClient with the cached client that is already used instead of the custom shared informers. With this, we will use only one client in both proxy and reg-service which is cached and optimized.

I'm changing the implementation of the methods only to minimize the scope of the changes in the PR.

Changes in unit-tests and removal of the extra layers will be addressed in many following (and most likely huge) PRs 😬

KUBESAW-133

[codecov]

Codecov Report

Attention: Patch coverage is 34.00000% with 33 lines in your changes missing coverage. Please review.

Project coverage is 81.17%. Comparing base (d7ff96d) to head (1b982c6).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
pkg/kubeclient/client.go	64.00%	9 Missing ⚠️
pkg/kubeclient/signup.go	0.00%	6 Missing ⚠️
pkg/kubeclient/banneduser.go	0.00%	4 Missing ⚠️
pkg/kubeclient/mur.go	0.00%	3 Missing ⚠️
pkg/kubeclient/socialevent.go	0.00%	3 Missing ⚠️
pkg/kubeclient/space.go	0.00%	3 Missing ⚠️
pkg/kubeclient/spacebinding.go	0.00%	2 Missing ⚠️
pkg/kubeclient/toolchainstatus.go	0.00%	2 Missing ⚠️
pkg/server/in_cluster_application.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #462      +/-   ##
==========================================
+ Coverage   79.46%   81.17%   +1.71%     
==========================================
  Files          42       42              
  Lines        2727     2630      -97     
==========================================
- Hits         2167     2135      -32     
+ Misses        471      407      -64     
+ Partials       89       88       -1     

Flag	Coverage Δ
unittests	81.17% <34.00%> (+1.71%)	⬆️

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[alexeykazakov]

+68 -221 I like this ratio for these reg-service refactoring PRs :)

[mfrancisc]

Nice cleanup 👍

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: alexeykazakov, MatousJobanek, mfrancisc, xcoulon

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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud