deps(pandas-gbq): drop Python 3.9

[tswast]

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Fixes internal b/490130968 🦕

[gemini-code-assist]

Code Review

This pull request updates the minimum supported Python version from 3.9 to 3.10 and increases the minimum version requirements for several core dependencies, including numpy, pandas, pyarrow, geopandas, and Shapely. Additionally, it replaces the Python 3.9 testing constraints file with a new version for Python 3.10 to reflect these updated lower bounds. I have no feedback to provide.

[tswast]

Oh, I see that 3.9 tests are still present. Perhaps this needs to change repo-wide?

[daniel-sanche]

We are in the process of moving off 3.9 across the repo, but probably won't finish it until Next

It looks like 3.9 is still in the noxfile here though? You could try removing it, or adding a session.skip if 3.9 is triggered (but if you keep it, you'd have to change this line in the prerelease_deps too, to point to 3.10)