🔨 Try out v3 actions

.github/workflows/test-builds.yml

     steps:
 
     - name: Check out the PR
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
 
     - name: Cache pip
-      uses: actions/cache@v2
+      uses: actions/cache@v3
       with:
         path: ~/.cache/pip
         key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
           ${{ runner.os }}-pip-
 
     - name: Cache PlatformIO
-      uses: actions/cache@v2
+      uses: actions/cache@v3
       with:
         path: ~/.platformio
         key: ${{ runner.os }}-${{ hashFiles('**/lockfiles') }}
 
     - name: Select Python 3.7
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v3
       with:
         python-version: '3.7' # Version range or exact version of a Python version to use, using semvers version range syntax.
         architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified