Bump astroid test requirement to 2.4.0
Older versions trigger an error on wrapt dependency:
https://github.com/PyCQA/astroid/issues/755
Bump pylint accordingly to new astroid
Fix some new PEP8 warnings appearing with new versions, and filter out
the larget I202 "Additional newline in a group of imports" one for now
Drop psutil from functional requirements, it indicated an old version
and we have it in common requirements now
Bump a series of lower-constraints and requirements to work with new pip
resolver, testing with steps outlined at:
http://lists.openstack.org/pipermail/openstack-discuss/2020-December/019285.html
This includes eventlet 0.22.1, previous versions triggered a hard to
track error on enum34
Cap cryptography in lower-constraints to prevent discovery failure in
relevant job (other jobs have it capped via upper-constraints)
Change-Id: Ie74ea517a403e6e2a7a4e0a245dd20e5281339e8
Closes-Bug: #1907242
8d6c301301