fix(powershell): remove mentions of USOClient

src/steps/os/windows.rs

@@ -235,10 +235,10 @@ pub fn windows_update(ctx: &ExecutionContext) -> Result<()> {
         powershell.windows_update(ctx)
     } else {
         print_warning(t!(
-            "Consider installing PSWindowsUpdate as the use of Windows Update via USOClient is not supported."
+            "The PSWindowsUpdate PowerShell module isn't installed so Topgrade can't run Windows Update.\nInstall PSWindowsUpdate by running `Install-Module PSWindowsUpdate` in PowerShell."
         ));
 
-        Err(SkipStep(t!("USOClient not supported.").to_string()).into())
+        Err(SkipStep(t!("PSWindowsUpdate is not installed").to_string()).into())
     }
 }