Fix lint-clang-format job (#47)

.github/workflows/ci.yaml

@@ -22,13 +22,19 @@ jobs:
     env:
       esphome_directory: esphome
     runs-on: ubuntu-latest
-    # cpp lint job runs with esphome-lint docker image so that clang-format-*
-    # doesn't have to be installed
-    container: esphome/esphome-lint:latest
     steps:
       - uses: actions/checkout@v2
-      # Set up the pio project so that the cpp checks know how files are compiled
-      # (build flags, libraries etc)
+      - name: Set up Python
+        uses: actions/setup-python@v2
+        with:
+          python-version: '3.9'
+      - name: Cache pip modules
+        uses: actions/cache@v1
+        with:
+          path: ~/.cache/pip
+          key: esphome-pip-3.9-${{ hashFiles('setup.py') }}
+          restore-keys: |
+            esphome-pip-3.9-
 
       - name: 💣 Clone esphome project
         run: git clone https://github.com/esphome/esphome.git
@@ -41,6 +47,14 @@ jobs:
           git commit -a -m "Add external component"
         working-directory: ${{ env.esphome_directory }}
 
+      - name: Add missing requirements
+        run: pip3 install setuptools wheel
+      - name: Set up python environment
+        run: VIRTUAL_ENV=false script/setup
+        working-directory: ${{ env.esphome_directory }}
+
+      # Set up the pio project so that the cpp checks know how files are compiled
+      # (build flags, libraries etc)
       - name: Set up platformio environment
         run: pio init --ide vscode
         working-directory: ${{ env.esphome_directory }}