Add support for InstallationToken in kubelogininstallerV0

[zhangyuan]

Context

When Github Connection uses InstallationToken, the task raises error.

Task Name

KubeloginInstallerV0

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Description

If the scheme of githubEndpointObject is InstallationToken, return AccessToken

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Risk Assessment (Low / Medium / High)

Assess the level of risk and provide reasoning (e.g., scope, impact, backward compatibility).

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Change Behind Feature Flag (Yes / No)

No.

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Tech Design / Approach

N/A

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Documentation Changes Required (Yes/No)

No.

The document incides it supports InstallationToken, actually not. So no updates to documents.

    {
      "name": "gitHubConnection",
      "type": "connectedService:github:OAuth,OAuth2,PersonalAccessToken,InstallationToken,Token",
      "label": "GitHub Connection",
      "defaultValue": "",
      "required": false,
      "helpMarkDown": "A GitHub connection is needed to prevent anonymous requests limits to the Github API for [Azure/kubelogin](https://github.com/azure/kubelogin) from impacting the installation. Leaving this empty may cause failures if the request limit is reached. This connection does not require ANY permissions."
    }

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Unit Tests Added or Updated (Yes / No)

No.

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Additional Testing Performed

List all other tests performed (manual or automated, including integration, regression, scenario tests, etc.).

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Logging Added/Updated (Yes/No)

No.

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Telemetry Added/Updated (Yes/No)

No.

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Rollback Scenario and Process (Yes/No)

No.

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Dependency Impact Assessed and Regression Tested (Yes/No)

No.

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Checklist

• Related issue linked (if applicable)
• Task version was bumped — see versioning guide
• Verified the task behaves as expected

[zhangyuan]

@microsoft-github-policy-service agree

[zhangyuan]

I don't have permissions to install non-official tasks to our origination, so I can't validate the change. I'm not sure if Azure DevOps can well handle InstallationToken from Github. Can someone point me how to validate?