update testing matrix

Author: imrehg

.github/workflows/tests.yaml

@@ -14,11 +14,11 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python: [3.7, 3.8, 3.9, '3.10', 3.11]
+        python: [3.9, '3.10', '3.11', '3.12', '3.13']
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: Setup Python
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python }}
       - name: Install Tox
@@ -32,11 +32,11 @@ jobs:
       matrix:
         linter: [flake8, black, license]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: Setup Python
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@v5
         with:
-          python-version: 3.9
+          python-version: 3.11
       - name: Install Tox
         run: pip install tox
       - name: Run linter