JIRA:EDUCATOR-4242

The pinned version is the one tagged with a release that is also on
PyPI.

https://github.com/jazzband/django-pipeline/tree/1.5.3

Use PyPI instead since that will be faster.

This has the effect of preventing Open edX installations from having
details which should be in configuration (because they're
edx.org-specific) end up in their applications.

revert pillow version

was causing issues with PT exam configuration dashboard launch

This reverts commit 544c7f7e.

This is necessary to allow new proctoring backends to mark proctored
attempts in error, often due to unuploaded files from the application
or issues with multiple sets of files attached to the same testing
session.

Fixes: https://openedx.atlassian.net/browse/INCR-16

- Remove second_review_required step for failed onboarding exams
- Timed-out exams should also trigger automatic file upload

JIRA:EDUCATOR-4153 and JIRA:EDUCATOR-4162, respectively