Update testing_pr.yml

Author: ndem0

.github/workflows/testing_pr.yml

@@ -58,4 +58,6 @@ jobs:
     - name: Test with pytest on Linux/MacOS
       shell: bash -el {0}
       if: startsWith(matrix.os, 'windows') != true
-      run: python -m pytest
+      run: |
+        conda activate occ
+        python -m pytest