Add nessai to containers

This merge request ads nessai to the template used to generate the docker files which is needed for the tests to pass for !921 (merged).

I've regenerated the docker files for each python version using the included script write_dockerfiles.py

approved this merge request

approved this merge request

changed milestone to %1.1.0

added Infrastructure Sampling labels

merged

mentioned in commit 9ff844de

mentioned in merge request !928 (merged)