CI: use cache provided by setup-python

Also, set lts node version

Author: amureki

.github/workflows/ci.yml

@@ -22,12 +22,9 @@ jobs:
     steps:
       - uses: actions/setup-python@v2.3.1
       - uses: actions/checkout@v2.4.0
-      - uses: actions/cache@v2.1.7
         with:
-          path: ~/.cache/pip
-          key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
-          restore-keys: |
-            ${{ runner.os }}-pip-
+          cache: 'pip'
+          cache-dependency-path: 'requirements.txt'
       - run: python -m pip install -r requirements.txt
       - run: ${{ matrix.lint-command }}
 
@@ -37,6 +34,8 @@ jobs:
       - run: sudo apt install -y gettext
       - uses: actions/setup-python@v2.3.1
       - uses: actions/setup-node@v2.5.0
+        with:
+          node-version: 'lts/*'
       - uses: actions/checkout@v2.4.0
       - name: Install Python dependencies
         run: python -m pip install --upgrade pip setuptools wheel twine readme-renderer
@@ -51,6 +50,9 @@ jobs:
     steps:
       - uses: actions/setup-python@v2.3.1
       - uses: actions/checkout@v2.4.0
+        with:
+          cache: 'pip'
+          cache-dependency-path: 'requirements.txt'
       - run: python -m pip install --upgrade pip setuptools wheel
       - run: python -m pip install -r requirements.txt
       - run: python setup.py develop