Set upper limits on our dependencies

[jni]

Description

NumPy has written a guide for downstream libraries setting upper bound version constraints. See this mailing list post:

https://mail.python.org/pipermail/numpy-discussion/2021-March/081572.html

and the two links therein:

https://numpy.org/devdocs/user/depending_on_numpy.html

and

http://scipy.github.io/devdocs/dev/core-dev/index.html#updating-upper-bounds-of-dependencies

I haven't had time to read them in detail but noting it here so we can follow the ecosystem.