Myth Auth LoginFilter Problem

@paulbalandan I have edited the composer.json entry in the root of my site and then tried to update Myth/Auth.

It asked for GitHub token which I gave it then I get this error:

Code:

Install of myth/auth failed

                                                                                     
  [RuntimeException]                                                                 
  Failed to clone https://github.com/lonnieezell/myth-auth.git, git was not found,   
  check that it is installed and in your PATH env.                                   
                                                                                     
  xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools) 
  , missing xcrun at: /Library/Developer/CommandLineTools/usr/bin/xcrun

I have confirmed that Xcode CLI tools are installed.

Please help. what am I doing wrong?