Pass workdir parameter to `composer config`

[mxr576]

Fixes #246

Description

See #246

Motivation and context

See #246

How has this been tested?

How this can be tested? :thinking:

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

PR checklist

• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [ ] I have read the CONTRIBUTING.md document.
• [ ] I have added tests to cover my changes.

[mxr576]

This was POC that I ran locally and figured that this can be the root cause.

$ cd /tmp
$ composer config cache-dir

In ConfigCommand.php line 206:
                                                                   
  File "./composer.json" cannot be found in the current directory  
                                                                   

config [-g|--global] [-e|--editor] [-a|--auth] [--unset] [-l|--list] [-f|--file FILE] [--absolute] [-j|--json] [-m|--merge] [--append] [--source] [--] [<setting-key> [<setting-value>...]]

$ composer -d /mnt/files/local_mount/build config cache-dir # this is a composer project root
/home/wodby/.composer/cache

[mxr576]

Okay, so this is already addressed in #233