skymarshal is incompatible to the latest version of ply

[KOLANICH]

Describe the bug
In the latest version of ply API has changed (and that version is here for pretty long time). But the code in the repo (skymarshal component) still uses the API of the old version.

To Reproduce
Steps to reproduce the behavior, e.g.:

1. git clone https://github.com/dabeaz/ply
2. cd ply
3. python3 -m build -nwx .
4. sudo pip3 install --upgrade ./dist/*.whl
5. cd ../
6. git clone https://github.com/symforce-org/symforce
7. cd third_party/skymarshal
8. python3 -m buld -nwx .
9. sudo pip3 install --upgrade ./dist/*.whl
10. cd ../../
11. python3 -m buld -nwx .

Expected behavior
Should be compatible to all the new and the old API of ply.

Environment (please complete the following information):

• OS and version: Debian sid
• Python version 3.11
• SymForce Version c3d2f3c

[aaron-skydio]

We support the latest released version of ply on PyPI that I'm aware of, which is 3.11: https://pypi.org/project/ply/#history

We'd potentially be open to also supporting from-source installs of unreleased versions of ply, or some more recent release if there is one that I'm missing, if it isn't too annoying to support both versions (I don't think we'd drop support for the released version on PyPI). We'd be happy to take a look if you want to submit a PR, I'm not really sure how involved it is to support both