docker: add docker socket help for mac users

[tmorrell]

❤️ Thank you for your contribution!

Description

Adds some help info for diagnosing problems with Docker on a Mac.

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[fenekku]

Thanks! Pinging @Meowcenary who ran into this issue as well. Is that what worked for you Eric?

[Meowcenary]

Thanks! Pinging @Meowcenary who ran into this issue as well. Is that what worked for you Eric?

This was definitely an issue I ran into at some point in the past, but most recently it was just user error. I can't remember exactly what the underlying issue was, but I had Postgres running as a Homebrew service and that was interfering with the Postgres container.

[fenekku]

Can I let you backport this @tmorrell ? Thanks!