Change HOST from static to configurable setting

[hryvinskyi]

Im using remote docker (https://ddev.readthedocs.io/en/stable/users/topics/remote-docker/)
but plugin always use 127.0.0.1 host for db configuration
can we change this constant to a configuration?

[rfay]

Wow, I didn't know that anybody ever used that. I'd be interested in talking with you outside this issue about what you do with it and why and how it works for you. https://discord.com/invite/5wjP76mBJD

I'm not sure it's fair to ask this plugin to handle this very obscure use-case though.