Upgrade to latest nbformat 5.9.2

[ringohoffman]

When I try to run:

$ pip install -e .[gen,dev,docs]
...
ERROR: Cannot install None, nerfstudio[dev,docs,gen]==1.0.2 and open3d==0.18.0 because these package versions have conflicting dependencies.

The conflict is caused by:
    nerfstudio[dev,docs,gen] 1.0.2 depends on nbformat==5.5.0; extra == "docs"
    myst-nb 0.16.0 depends on nbformat~=5.0
    nbconvert 7.2.5 depends on nbformat>=5.1
    open3d 0.18.0 depends on nbformat>=5.7.0

This gets fixed by upgrading to the latest nbformat: https://pypi.org/project/nbformat/5.9.2/#history

[kerrj]

lgtm