Please adopt containerBackground API

After updating to the Xcode beta and build/running my app, I started to get an error on all my widgets "Please adopt containerBackground API" and I found a post that had a solution to accommodate iOS 14-16

import Foundation
import SwiftUI


extension View {
    @ViewBuilder
    func widgetBackground() -> some View {
        let gradient = LinearGradient(gradient: Gradient(colors: [Color("LightBlue"), Color("DarkBlue")]), startPoint: .topLeading, endPoint: .bottomTrailing)
        
        if #available(watchOS 10.0, iOSApplicationExtension 17.0, iOS 17.0, macOSApplicationExtension 14.0, *) {
            self.containerBackground(gradient, for: .widget)
        } else {
            self.background(gradient)
        }
    }
}

I add this to my ZStack for the widget and it does nothing. I still get the same error to adopt to containerBackground API. What am I doing wrong?