There's a merged pull request on the void-packages repository

python3-cypari2: sync version with upstream release tag
https://github.com/void-linux/void-packages/pull/40529

Description:
#### Testing the changes
- I tested the changes in this PR: **briefly**

#### Local build testing
- I built this PR locally for my native architecture, x86_64

@tornaria upstream released a tagged v2.1.3 tarball including changes in the patch. I added `python3-cysignals` under depends since it's mentioned under their [install_requires]( https://github.com/sagemath/cypari2/blob/2.1.3/setup.py#L70). Does this look okay to you?