validation suite fails to install on focal behind proxy

[Alexander Balderson]

When trying to install the validation suite on a focal machine behind a proxy the install hangs installing pynacl==1.1.2. This is with a proxy set in ~/.config/pip/pip.conf

It seems that this was never an issue on bionic, since pyncal's bionic version is 1.1.2, the install would use the existing version on our test systems.

Jason Hobbs found that the install fails because pyncal 1.1.2 uses setuptools to install cffi and flake8 and setuptools does not honor the proxy.

Additionally pip does not garotte that order of requirements files will be followed.

There seem to be a few workaround choices on focal:
1) change the requirements to be pynacl >= 1.1.2, this allows for using 1.3.0 from focal to run the test. I validated that the tests still run correctly using python3-nacl 1.3.0. I ran into a few problems running the tests on vsphere, but all of them have commits which fix them in the latest version of the validation suite.
2) set the tox.ini to install cffi and flake8 before anything else; See the attached patch from Jason
3) snap the suite so environment doesnt matter anymore.

[Alexander Balderson (asbalderson)]

attaching patch

[Jason Hobbs (jason-hobbs)]

it's actually surl that uses flake8; switching to a newer pynacl alone won't fix this

[Adam Stokes (adam-stokes)]

Applied to https://github.com/charmed-kubernetes/jenkins/commit/c7b59b7ae8c723d0f415f2afc6627018e50527fa