`Jinja2==3.1.0` breaks build workflow

[pmeier]

We use

vision/docs/requirements.txt

Line 5 in 56fb0bf

sphinx==3.5.4

Internally, they only restrict Jinja2>=2.3. Jinja2==3.1.0, which was released about an hour ago, removes

from jinja2 import environmentfilter

This however is imported by sphinx==3.5.4. Never versions of sphinx have a safeguard .

This trips our CI docs workflow. See this run for an example.

[adamjstewart]

Instead of supporting an obsolete version of Sphinx for the foreseeable future, why not use modern Sphinx? #5121

[pmeier]

The fix #5674 was quick way to get CI green again. In the long run, I agree, we should move to sphinx >= 4. But that is already tracked in the issue you mentioned.