ci: Bump checkout and setup-python to v5 for Node 24 compatibility

GitHub will force Node 24 for JS actions starting June 2nd, 2026.
v5 of both actions runs on Node 24 natively, removing the deprecation
warning.

Author: tysoncung

.github/workflows/test.yml

@@ -16,10 +16,10 @@ jobs:
         python-version: ['3.8', '3.9', '3.10', '3.11']
 
     steps:
-    - uses: actions/checkout@v4
-    
+    - uses: actions/checkout@v5
+
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}