Mega fix of brainrender

Description

What is this PR

[x] Bug fix
[ ] Addition of a new feature
[ ] Other

Why is this PR needed?

Brainrender is not currently easy to install on all OSs and with recent Python versions, and was therefore declared temporarily unsupported.

What does this PR do?

Collects changes from lots of smaller PRs that are connected with the overall goal of making brainrender functional and installable with Python 3.9, 3.10, 3.11 and newest (or at least recent) vedo (and newest other dependencies), so we can remove the current warning.

This includes

compatibility with vedo 2023.5.0/fixing rendering issues:
- 262
- 277
- 281
- 283
On CI, updates to successfully install brainrender across OSs with NEP 29 Python versions, and get tests to pass:
- 265
- 287
- 254
- 260
- 265
- 273
- 275
- 276
- 287
tidying up/documenting this changes

References

See issues closed in PRs above, and the milestone for this project.

How has this PR been tested?

While the tests would certainly warrent improvement, the "fast" tests now all run on CI across OSs
@IgorTatarnikov and I have tested extensively manually across OSs, and while we are aware of more possible improvements, we feel this is at a sensible stage to support users again.

Is this a breaking change?

Yes, in that we now support Python 3.9, 3.10 and 3.11 instead of Python <=3.8

Does this PR require an update to the documentation?

See "tidying up/documenting this changes" bullet points above.

Checklist:

[x] The code has been tested locally
[x] (Kind of) Tests have been added to cover all new functionality (unit & integration)
[x] The documentation has been updated to reflect any changes
[x] The code has been formatted with pre-commit

brainglobe / brainrender