Try ubuntu-22.04 in place of ubuntu-20.04

This is what numpy uses, I think.

Author: peterjc

.github/workflows/cibuildwheel.yml

@@ -9,7 +9,7 @@ jobs:
     strategy:
       matrix:
         # macos-13 is an intel runner, macos-14 is apple silicon
-        os: [ubuntu-20.04, windows-2022, macos-13, macos-14]
+        os: [ubuntu-22.04, windows-2022, macos-13, macos-14]
     env:
       # Seems to have trouble parsing our setup.py, thus:
       CIBW_PROJECT_REQUIRES_PYTHON: ">=3.10"