update sys matrix to skip intended Py versions on Linux and Win

Author: slayoo

.github/workflows/tests+artifacts+pypi.yml

@@ -17,10 +17,13 @@ jobs:
     strategy:
       matrix:
         platform: [ubuntu-latest, macos-latest, windows-latest]
-        python-version: ["3.8", "3.10"]
+        python-version: ["3.7", "3.8", "3.10"]
+        exclude:
+          - platform: ubuntu-latest
+            python-version: "3.7"
         exclude:
           - platform: windows-latest
-            python-version: "3.10"
+            python-version: ["3.8", "3.10"]
     runs-on: ${{ matrix.platform }}
     steps:
       - if: matrix.platform == 'macos-latest'