docker-compose templating breaks email sending

[yanokwa]

In https://github.com/getodk/central/blob/master/docker-compose.yml#L60, we use this syntax:

EMAIL_FROM=${EMAIL_FROM:-no-reply@${DOMAIN}}`

Given an address of foo@bar.org, password resets fail (stack trace) with this error:

Mail command failed: 501 Syntax error, parameters in command "MAIL FROM:<foo@bar.org}>" unrecognized or missing

Note the trailing } in the email. Somewhere the templating is failing. This is confirmed by running docker compose config

[lognaturel]

I recall verifying this extensively because it is strange but maybe my memory is playing tricks on me. Could it be a docker compose version difference?