cleverage/eav-manager: cannot use a SSH git repository

This command executed in the container fails :

```bash
/app $ git clone --no-checkout 'git@git.example.com:xxx/yyy.git' '/app/vendor/xxx/yyy' 
Cloning into '/app/vendor/xxx/yyy'...
fatal: cannot run ssh: No such file or directory
fatal: unable to fork
```