Being able to set CORS with a .env variable would be nice

[noahwsmith]

To support inter-institutional collaboration, sometimes setting non-default values for CORS is necessary. Currently to do this requires bindmounting a copy of https://github.com/Islandora-Devops/isle-buildkit/blob/main/drupal/rootfs/etc/confd/templates/drupal.fpm.conf.tmpl and inserting into that template.

I believe that this is enough of a "standard use case" that we should support it with a .env variable. I will issue a PR momentarily to address this.

[noahwsmith]

What I've done is the VERY SIMPLE version that lets you set a single domain, or *. We could also look at a more complex situation where you pass in a regex that sets a list of allowed domains since you cannot just give it a list in string format. For example: kubernetes/ingress-nginx#5496

[noahwsmith]

See comment in #334 for alternate solution inside of Drupal.