fix(ci): upgrade actions and Python versions

- Upgrade actions/checkout from v3 to v5
- Upgrade actions/setup-python from v3 to v6
- Remove Python 3.8 (not available on ubuntu-latest)
- Add Python 3.12 and 3.13 to test matrix
- Update publish workflow to use Python 3.9

Fixes pip cache 400 error caused by outdated actions/setup-python@v3

Author: olgahaha

.github/workflows/build.yml

@@ -12,12 +12,12 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest]
-        python-version: ['3.8', '3.9', '3.10', '3.11']
+        python-version: ['3.9', '3.10', '3.11', '3.12', '3.13']
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v5
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v6
       with:
         python-version: ${{ matrix.python-version }}
         cache: 'pip'

.github/workflows/python-publish.yml

@@ -14,11 +14,11 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v5
     - name: Set up Python
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v6
       with:
-        python-version: '3.8'
+        python-version: '3.9'
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip