tests: workaround for missing ffmpeg in macos-latest M1

.github/workflows/check.yml

@@ -32,6 +32,22 @@ jobs:
       uses: actions/setup-python@main
       with:
         python-version: ${{ matrix.python-version }}
+    # Temporary fix for 'pip install imageio-ffmpeg'
+    # not including the FFMPEG binary on Apple Silicon macs
+    # This step can be removed when issue is fixed in imageio-ffmpeg
+    # https://github.com/imageio/imageio-ffmpeg/issues/71
+    - name: Setup FFmpeg
+      if: runner.name == 'macos-latest'
+      run: |
+        brew update
+        brew install ffmpeg
+    # Temporary fix for 'pip install imageio-ffmpeg'
+    # not including the FFMPEG binary on Apple Silicon macs
+    # This step can be removed when issue is fixed in imageio-ffmpeg
+    # https://github.com/imageio/imageio-ffmpeg/issues/71
+    - name: Setup FFmpeg
+      if: runner.os == 'macOS'
+      uses: AnimMouse/setup-ffmpeg@v1
     - name: Install dependencies
       run: |
         # prerequisites