update action versions and cache

.github/workflows/gh-pages.yml

@@ -6,33 +6,17 @@ jobs:
   deploy:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Install pandoc and doxygen 
         run: |
           sudo apt install pandoc doxygen
 
       - name: Setup Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
-          python-version: '3.10'
-
-      - name: Upgrade pip
-        run: |
-          # install pip=>20.1 to use "pip cache dir"
-          python3 -m pip install --upgrade pip
-
-      - name: Get pip cache dir
-        id: pip-cache
-        run: echo "::set-output name=dir::$(pip cache dir)"
-
-      - name: Cache dependencies
-        uses: actions/cache@v3
-        with:
-          path: ${{ steps.pip-cache.outputs.dir }}
-          key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
-          restore-keys: |
-            ${{ runner.os }}-pip-
+          python-version: '3.11'
+          cache: "pip"
 
       - name: Install dependencies
         run: python3 -m pip install -r ./requirements.txt