developer/api/v1/users/Grant-GroupsAuthorization.ps1

function Grant-GroupsAuthorization
{
    param(
        [Parameter(Mandatory)]
        [string] $AppAlias,
        [Parameter(Mandatory)]
        [string] $VersionAlias,
        [Parameter(Mandatory)]
        [string[]] $GroupIds,
        [Parameter(Mandatory)]
        [string] $PlanName
    )

    return Invoke-Api Post "/developer/api/v1/apps/$AppAlias/versions/$VersionAlias/groups" -JsonBody @{
        "groupIds" = $GroupIds
        "planName" = $PlanName
    }
}