Add support for python 3.10

[tlambert03]

No description provided.

[codecov]

Codecov Report

Merging #294 (b8b3c32) into main (2cd0fce) will decrease coverage by 0.04%.
The diff coverage is 80.00%.

@@            Coverage Diff             @@
##             main     #294      +/-   ##
==========================================
- Coverage   90.29%   90.24%   -0.05%     
==========================================
  Files          29       29              
  Lines        3297     3301       +4     
==========================================
+ Hits         2977     2979       +2     
- Misses        320      322       +2     

Impacted Files	Coverage Δ
magicgui/widgets/_bases/widget.py	87.36% <80.00%> (-0.28%)	⬇️
magicgui/widgets/_table.py	96.61% <0.00%> (-0.25%)	⬇️
magicgui/backends/_qtpy/widgets.py	86.01% <0.00%> (ø)

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