Install PSScriptAnalyzer from the PoshTestGallery, which is likely to get pushed to the PSGallery soon pending positive feedback

Install-PSScriptAnalyzerFromPoshTestGallery.ps1

try {
    Register-PackageSource -Name PoshTestGallery -Location https://www.poshtestgallery.com/api/v2/ -ProviderName PowerShellGet
    Install-Module PSScriptAnalyzer -Repository PoshTestGallery -Scope CurrentUser -Force
}
finally {
    Unregister-PSRepository -Name PoshTestGallery
}