Test on ubuntu-20.04, macos-latest, windows-latest

Author: hankcs

.github/workflows/unit-tests.yml

@@ -20,9 +20,11 @@ jobs:
         os: [ ubuntu-latest, macos-latest, windows-latest ]
         python-version: [ 3.6, 3.7, 3.8, 3.9, '3.10' ]
         exclude:
-          # GHA doesn't list 3.6 for ubuntu-22.04
+          # GHA doesn't list 3.6 and 3.7 for ubuntu-latest
           - os: ubuntu-latest
             python-version: "3.6"
+          - os: ubuntu-latest
+            python-version: "3.7"
 
           # MacOS 14.4.1 for arm64 doesn't support Python < 3.8
           - os: macos-latest
@@ -34,6 +36,8 @@ jobs:
           # GHA doesn't list 3.6 for ubuntu-22
           - os: ubuntu-20.04
             python-version: "3.6"
+          - os: ubuntu-20.04
+            python-version: "3.7"
 
           # MacOS 13 required for Python < 3.8
           - os: macos-13