Test Lilac upgrade on Staging

These things can be tested now on learn.staging.totem-project.org/login to make sure Lilac.1 works:

LMS:

• Log in on LMS
• Change password (check if you get an email for it)
• Send an email from a course
• Check at least one course with the following items in it:
  • A javascript problem (password checker, TOTP example and/or IP tool)
  • An INDie diagram
• Hidden courses
  • Open a hidden course in studio
  • Make a minor change to the advanced settings and save it
  • https://learn.totem-project.org/courses should not list the hidden course

Admin:

• Can you still use learn.totem-project.org/admin ?

Figures (removed)

- [ ] Can you still use learn.totem-project.org/figures ?

Developer checks:

• Verify that the edx fork (installed in ~/.local/share/tutor/build-images.sh) is the same version as tutor config printvalue OPENEDX_COMMON_VERSION`
• tutor local logs should not contain users' IP addresses