Misc fixes for wp-cli and autoinstall on Ubuntu WSL2.

[LiamKarlMitchell]

wpcli could not seem to connect as the environment variables were not set.

E.g. I had this in my ~/.bash_profile

alias wp="docker-compose run --rm wpcli"

Then tried to run wp post list

Which previously showed Error: Error establishing a database connection.

Confirmed by echoing the constants defined in the wp-config.php