Add conda containers into CI
See https://git.ligo.org/lscsoft/gstlal/container_registry/586. This creates containers with gstlal and friends available.
Maintenance will be performed on git.ligo.org, containers.ligo.org, and docs.ligo.org on Tuesday 23 April 2024 starting at approximately 9am PDT. It is expected to take around twenty minutes and there will be several periods of downtime throughout the maintenance. Please address any comments, concerns, or questions to the helpdesk.
See https://git.ligo.org/lscsoft/gstlal/container_registry/586. This creates containers with gstlal and friends available.