Add user for cli image.

[torounit]

Description

Add user xfs for cli docker image.
cli user www-data. But user of mounted volume is xfs. So unable to create directory and file from cli commands.

see: docker-library/wordpress#256

How has this been tested?

$ docker-compose run cli wp plugin install wordpress-importer

Screenshots

Types of changes

Bug fix (non-breaking change which fixes an issue)

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• My code has proper inline documentation.

[pento]

Excellent, I'd totally been running into this problem. Thank you for the simple fix, @torounit!