Update testing.yml

Author: alexlib

.github/workflows/testing.yml

@@ -19,7 +19,7 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install flake8 pytest
+        pip install openpiv flake8 pytest
         if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
 #     - name: Lint with flake8
 #       run: |