Replace Python 3.6, 3.7 with 3.9, 3.10

Author: hagenw

.github/workflows/test.yml

@@ -9,12 +9,12 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macOS-latest, windows-latest]
-        python-version: [3.6, 3.7, 3.8]
+        python-version: [3.8, 3.9, 3.10]
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
     - name: Prepare Ubuntu

setup.py

@@ -31,8 +31,9 @@
         "Operating System :: OS Independent",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.6",
-        "Programming Language :: Python :: 3.7",
+        "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
+        "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3 :: Only",
         "Topic :: Scientific/Engineering",
     ],