Better documentation for kubectl and azad-proxy plugin

[simongottschlag]

When following the installation guide, it's not obvious how to install kubectl and the azad-proxy plugin installation from krew is a bit down in the azad-kube-proxy documentation. We should add som docs to make this process easier to follow.

I've added some comments about how I got it working on a Windows 11 machine.

[simongottschlag]

We should recommend installing winget for Windows: https://apps.microsoft.com/store/detail/app-installer/9NBLGGH4NNS1

Then it's just running winget install -e --id Kubernetes.kubectl to install the kubectl client.

[simongottschlag]

Krew requires git wich isn't installed by default on Windows, but can easily be installed if you have winget using: winget install -e --id Git.Git

[simongottschlag]

Krew can't be installed using winget, but easily done using:

$latestVersion = (Invoke-WebRequest "https://github.com/kubernetes-sigs/krew/releases/latest").BaseResponse.ResponseUri.OriginalString.split('/')[-1]
curl.exe -LO "https://github.com/kubernetes-sigs/krew/releases/download/$latestVersion/krew.exe"
curl.exe -LO "https://github.com/kubernetes-sigs/krew/releases/download/$latestVersion/krew.exe.sha256"

Now validate that the downloaded version have the correct hash: $(Get-FileHash -Algorithm SHA256 .\krew.exe).Hash -eq $(Get-Content .\krew.exe.sha256)

Then continue with the install:

.\krew.exe install krew
rm krew.exe*
[Environment]::SetEnvironmentVariable("PATH", $Env:PATH + ";%USERPROFILE%\.krew\bin", [EnvironmentVariableTarget]::User)

Restart the shell/terminal and then install azad-proxy:

kubectl krew install azad-proxy