update pixi toml and add default value for sessions

Elisabetta Pianorirequested to merge
ep/fix_session_error into main

If no value is set for session_name in user_config, trying to interact with the viewer will make it crash. This is due to !368 (merged) I added a default value for SESSION_COOKIE_NAME in case it's not set in the config file.

I also updated the pixi config to match the requirements-pip.txt file.

More detailed description

Checklist

  • label this MR
  • assign reviewers
  • update documentation and changelog
  • link related issues and close with this MR via "closes #"
Edited by Elisabetta Pianori

Merge request reports