Add docker.for.mac.localhost to allowed hosts for dev

What does this MR do and why?

Adds docker.for.mac.localhost to the list of allowed hosts so containers which require calls to Rails API can do that. For example Triage Ops project needs it. Other various projects which are designed to be run in a container will need it too when you Rails app is not in the docker.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.