feat: RBAC support for external argo/flux apps

[vivekanandan-devtron]

Description

Fixes #7007

Checklist:

• The title of the PR states what changed and the related issues number (used for the release note).
• Does this PR requires documentation updates?
• I've updated documentation as required by this PR.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have tested it for all user roles.
• I have added all the required unit/api test cases.

Does this PR introduce a user-facing change?

[github-actions]

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[bito-code-review]

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[sonarqubecloud]

Quality Gate passed

Issues
18 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 SonarQube Cloud