This change updates several dependencies that are outdated in various

ways:
Python:

cryptography and pyOpenSSL are updated to the latest
Pygments is updated to the latest (with some matching unit test

  changes)
markdown and pymdown-extensions are updated to the latest version for

  Python 3.10+, with fallbacks for older pythons.
django-haystack is updated to the latest, and our backports of the

  elasticsearch backend have been removed.

JS:

@prantlf/jsonlint is updated to the latest, and its sub-dependency

ajv is pinned to a slightly newer version to cover a new security fix.
jquery-ui is updated to the latest.

Did an editable install and ran unit tests.