CI failing due to Sphinx/Jinja mismatch

Package version (if known): master

## Describe the bug
Sphinx 3 is being installed, which is incompatible with Jinja 3.

## Steps to Reproduce
1. Go to https://github.com/inveniosoftware/dictdiffer/runs/7955284018

## Expected behavior

## Screenshots (if applicable)
```py
Run ./run-tests.sh
./run-tests.sh
lists of files in version control and sdist match
Traceback (most recent call last):
File "/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/runpy.py", line 197, in _run_module_as_main
return _run_code(code, main_globals, None,
File "/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/runpy.py", line 87, in _run_code
exec(code, run_globals)
File "/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/site-packages/sphinx/cmd/build.py", line 25, in
from sphinx.application import Sphinx
File "/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/site-packages/sphinx/application.py", line 42, in
from sphinx.registry import SphinxComponentRegistry
File "/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/site-packages/sphinx/registry.py", line 24, in
from sphinx.builders import Builder
File "/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/site-packages/sphinx/builders/__init__.py", line 26, in
from sphinx.util import import_object, logging, rst, progress_message, status_iterator
File "/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/site-packages/sphinx/util/rst.py", line 22, in
from jinja2 import environmentfilter
ImportError: cannot import name 'environmentfilter' from 'jinja2' (/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/site-packages/jinja2/__init__.py)
```

## Additional context