github action: run tests on 22.04 for py37 support

Author: fliiiix

.github/workflows/main.yml

@@ -24,7 +24,7 @@ jobs:
       max-parallel: 8
       matrix:
         python-version: [3.7, 3.13]
-        os: [ubuntu-latest, windows-latest, macOS-latest]
+        os: [ubuntu-22.04, windows-latest, macos-latest]
         exclude:
         - os: macos-latest
           python-version: 3.7