Add pycbc to Python dependencies in tests.yml

Author: RoxGamba

.github/workflows/tests.yml

@@ -26,7 +26,7 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install flake8 pytest sxs romspline
+        pip install flake8 pytest sxs romspline pycbc
         if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
     #- name: Lint with flake8
     #  run: |