Update tests.yml

.github/workflows/tests.yml

@@ -123,11 +123,13 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v2
       with:
-        python-version: '2.x'
+        python-version: '3.x'
     - name: Install dependencies
       run: |
+        python -m pip install pip==19.3.1
+        pip install --upgrade setuptools wheel
         python --version
-        python -m pip install --upgrade pip setuptools wheel
+        pip --version
     - name: Install Wasienv
       run: curl https://raw.githubusercontent.com/wasienv/wasienv/master/install.sh | sh
     - name: Install Wasmer