Adds user_agent to endpoint.ex in the README (#676)
Adds user_agent to endpoint.ex in the README (#676)

* Adds user_agent to endpoint configuration

* Reformat `...`

Co-authored-by: Mitchell Hanberg <b2b9d047cb15a4ee2f66e3be0a97e512d2f22473@mitchellhanberg.com>

Co-authored-by: Mitchell Hanberg <b2b9d047cb15a4ee2f66e3be0a97e512d2f22473@mitchellhanberg.com>
keathley/wallaby,keathley/wallaby