fix(docs): Improve powershell command for setup script for failure cases

docs/docs/user-setup.md

@@ -82,7 +82,7 @@ bash -c "$(wget https://zmk.dev/setup.sh -O -)" '' --wget
 <TabItem value="PowerShell">
 
 ```
-iex ((New-Object System.Net.WebClient).DownloadString('https://zmk.dev/setup.ps1'))
+powershell -Command "iex ((New-Object System.Net.WebClient).DownloadString('https://zmk.dev/setup.ps1'))"
 ```
 
 </TabItem>