Why can't the yarn command in vscode be used?

  Since the integrated terminal in vscode uses powershell, we need to set the execution permissions of powershell.

Solution:

1. Enter the C:\Windows\System32\WindowsPowerShell\v1.0 directory and find the powershell.exe file.
2. Right-click the file and execute it with administrator rights.
   
3. Execute the set-ExecutionPolicy RemoteSigned command and enter the y option.
   
4. Restart vscode