* A modal used to collect demographics information

Add checkmark to final page (#24957)

Remove themeing to get ready for staging

MICROBA-574 | Dismiss CTA after learner finishes answering modal questions (#24965)

[MICROBA-574]
- Dismiss CTA after learner finishes answering demographics questions
- Cleanup comments

* Various initial bugfixes

- fixes 2 issues with the multiselect dropdown erasing state
- prevents input higher than 255 characters in the self describe
- fixes 400 errors when the user selects a default option
- Removes additional page count section

- Re-adding deleted JS file. Can't clean this up until after we cutover to using the new Demographics modal

* Add translatable string to clear button

* Remove extra page counter from the header for the third time

* Remove unneeded template context

Co-authored-by: Matt Tuchfarber <mtuchfarber@edx.org>
Co-authored-by: Justin Hynes <jhynes@edx.org>