pyScss via django-pycss is incompatible with Python 3.10

[Ian Wienand]

In testing devstack against Fedora 35, which uses Python 3.10, we found an error starting Horizon

---
File "/usr/local/lib64/python3.10/site-packages/scss/types.py", line 6, in <module>
 from collections import Iterable
---

It looks like this comes in via django-pyscss [2] which pulls in pyScss; it seems there's a pull request on this that hasn't been responded to at [3]

We've disabled Horizon in Fedora 35 for now, but reverting [1] will give an environment for further testing

[1] https://review.opendev.org/c/openstack/devstack/+/827576
[2] https://pypi.org/project/django-pyscss/#description
[3] https://github.com/Kronuz/pyScss/pull/411

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/horizon/+/830618

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/horizon/+/830618
Committed: https://opendev.org/openstack/horizon/commit/e6d46b218c04c4486988f2c1a422e7e00b14c2df
Submitter: "Zuul (22348)"
Branch: master

commit e6d46b218c04c4486988f2c1a422e7e00b14c2df
Author: manchandavishal <email address hidden>
Date: Wed Feb 23 19:30:19 2022 +0530

    Update pyScss to 1.4.0

    pyscss v1.3.7 doesn't work with python 3.10. So this patch bump
    pyscss version to latest i.e. v1.4.0 so it can support python 3.10
    and consume other fixes included in pyscss v1.4.0.

    Closes-Bug: #1960204
    Depends-On: https://review.opendev.org/c/openstack/requirements/+/830615
    Change-Id: I764aa5491df8c8d39f4f168241f91d19ce7fed26

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/horizon 22.2.0 release.