CI: Enable testing with Python 3.11 (#284)

Author: intgr

.github/workflows/test.yml

@@ -31,7 +31,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ['3.7', '3.8', '3.9', '3.10']
+        python-version: ['3.7', '3.8', '3.9', '3.10', '3.11']
     steps:
       - uses: actions/checkout@v3
       - name: Setup system dependencies
@@ -54,7 +54,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ['3.7', '3.8', '3.9', '3.10']
+        python-version: ['3.7', '3.8', '3.9', '3.10', '3.11']
     steps:
       - uses: actions/checkout@v3
       - name: Setup system dependencies