reduce test matrix again

Author: theOehrly

.github/workflows/python-app.yml

@@ -33,14 +33,14 @@ jobs:
       matrix:
         python-version: [ "3.8", "3.9", "3.10", "3.11", "3.12" ]
         sphinx-version: [
-          "7.0.*", "7.1.*", "7.2.*",
-          "6.0.*",
-          "5.0.*",
-          "4.5.*"
+          "7.0.*",  # possible range: 7.0.0 - 7.4.7
+          "6.0.*",  # possible range: 6.0.0 - 6.2.1
+          "5.0.*",  # possible range: 5.0.0 - 5.3.0
+          "4.5.*"   # possible range: 4.5.0, also latest that supports py3.8
         ]
-        exclude:
-          - python-version: "3.8"
-            sphinx-version: "7.2.*"
+        include:
+          - python-version: "3.9"
+            sphinx-version: "7.2.*"  # latest version that supports py3.9
     uses: ./.github/workflows/build.yml
     with:
       python-version: ${{ matrix.python-version }}
@@ -62,7 +62,7 @@ jobs:
       matrix:
         python-version: [ "3.8", "3.9" ]
         sphinx-version: [
-          "4.4.*", "4.3.*", "4.2.*", "4.1.*", "4.0.*"
+          "4.0.*"  # possible range: 4.0.0 - 4.4.0
         ]
     uses: ./.github/workflows/build.yml
     with:
@@ -85,8 +85,11 @@ jobs:
       matrix:
         python-version: [ "3.7", "3.8", "3.9" ]
         sphinx-version: [
-          "3.5.*", "3.4.*", "3.2.*",  "3.1.*", "3.0.*",
+          "3.0.*",  # possible range: 3.0.0 - 3.5.4
         ]
+        include:
+          - python-version: "3.7"
+            sphinx-version: "3.5.*"  # latest version that supports py3.7
     uses: ./.github/workflows/build.yml
     with:
       python-version: ${{ matrix.python-version }}