Cleanup unused CONFIG_ROOT variable and dead code.

Add logs in get_problem_responses

Python Requirements Update

* Commits:
  Log and skip empty children when rendering library_content

instead of throwing an exception on None-access.

Fix issues with video transcript panel

[BD-05] [TNL-7308] Add ORA Zipped File Download for Submission Text + Attached Files

Allow entitlements to be used past the course has ended but
upgrade deadline is still in future for already enrolled
learners.

PROD-1497

disable xsslint on program_header_view

This fixes a bug where the video transcripts panel would be open on
page load even when no transcripts were present. It also cleans up the
code a bit to remove unused cookies and tries to reduce flickering of
the transcript panel.

python -m edx_repo_tools.modernize_openedx_yaml --path=openedx.yaml
The following packages were installed: git+https://github.com/edx/repo-tools.git@4ac2ffde02b6df4bf633f7b88966137d71233bb1.

Ratelimit the registration endpoint

Python Requirements Update

update edxval

From what I've gleaned, CONFIG_FILE (and LMS_CFG and STUDIO_CFG
environment variables) supercedes CONFIG_ROOT.  There's no code anymore
that reads the value of the CONFIG_ROOT django setting, and in turn the
CONFIG_ROOT environment variable.

Tangentially related to DENG-369

Fix double-wrapped exception in capa/inputtypes.py

Disable caching in forum home

It is already enabled in devstack LMS, stage LMS/Studio,
and prod LMS/Studio.

However, it is currently disabled in edge LMS/Studio,
and as far as I know, sandbox LMS/Studio as well as the
default Open edX LMS/Studio.

We would like to move towards enabling it globally by
default, and enabling it in devstack Studio would be
a first step towards that.

Disable updating Library Content children during import