Add support for non-OpenShift K8s to managed-gitops, testing via k3d

[jgwest]

Description:

• Add support for non-OpenShift K8s to managed-gitops, primarily by removing references to Routes and ArgoCD CR
• Add initial testing via k3d

Link to JIRA Story (if applicable): N/A

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jgwest

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• OWNERS [jgwest]

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[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

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

See analysis details on SonarQube Cloud

[openshift-ci]

@jgwest: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/managed-gitops-e2e-tests	7b5aac9	link	true	/test managed-gitops-e2e-tests
ci/prow/images	7b5aac9	link	true	/test images

Full PR test history. Your PR dashboard.

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[codecov]

Codecov Report

Attention: Patch coverage is 57.14286% with 3 lines in your changes missing coverage. Please review.

Project coverage is 60.80%. Comparing base (017be24) to head (7b5aac9).
Report is 39 commits behind head on main.

Files with missing lines	Patch %	Lines
cluster-agent/utils/argocd_login_credentials.go	57.14%	1 Missing and 2 partials ⚠️

❌ Your project check has failed because the head coverage (60.80%) is below the adjusted base coverage (62.60%). You can increase the head coverage or adjust the Removed Code Behavior.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #838      +/-   ##
==========================================
- Coverage   62.76%   60.80%   -1.97%     
==========================================
  Files          98       99       +1     
  Lines       18914    19053     +139     
==========================================
- Hits        11872    11585     -287     
- Misses       5722     6150     +428     
+ Partials     1320     1318       -2     

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