Refs #265. Fix typo

Author: kylegibson-rldatix

.github/workflows/ci.yml

@@ -30,7 +30,7 @@ jobs:
           run: |
             cd /workspace
             python --version
-            pip install -r requirements.txt
+            pip install --requirement requirements/testing.txt
             pip install -e .
             nosetests --with-doctest