Update Cellpose version to support Python 3.11

[jluethi]

We'll need to update Cellpose either to version 2.3.2 or a 3.x release (see #655) to get support for Python 3.11 (needed for ngio 0.2.0 support).

CC @lorenzocerrone

[tcompa]

I was confused about this issue, because we did run Cellpose on Python 3.11 (as part of testing the 1.5.0 pre-releases).

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The Cellpose=2.3.2 release notes say:

add python 3.11 support from @harryzcy (MouseLand/cellpose#807)

but the corresponding PR says:

Python 3.11 seems to be working just fine. Python 3.12 doesn't work because ...

and there was no code change in that PR (apart from the GitHub action that now also tests 3.11).

Thus the current required version seems OK with Python3.11 as well. Not a reason in itself for keeping it pinned, but at least it explains why it is working.

[jluethi]

@tcompa Thanks for reviewing this, I forgot that there was still this concern as well! Something to keep in mind for the testing of the Cellpose refactor then @lorenzocerrone