Closes #2150

This PR updates the cmd to default to the no colors mode if the NO_COLOR environment variable is set. This is to follow the informal standard https://no-color.org/ that states:

Command-line software which adds ANSI color to its output by default should check for a NO_COLOR environment variable that, when present and not an empty string (regardless of its value), prevents the addition of ANSI color.

Note that the user's CLI flags still override the default behaviour, as per the following:

User-level configuration files and per-instance command-line arguments should override the NO_COLOR environment variable. A user should be able to export NO_COLOR=1 in their shell configuration file as a default, but configure a specific program in its configuration file to specifically enable color.