Update GitHub action versions to resolve deprecation warnings

Author: kurtmckee

.github/workflows/test.yml

@@ -14,11 +14,11 @@ jobs:
     runs-on: ${{ matrix.platform }}
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v6
       with:
         submodules: recursive
     - name: Set up Python ${{ matrix.python }}
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v6
       with:
         python-version: ${{ matrix.python }}
     - name: Install test dependencies