Update the requirements file for our direct invocations of coverage
diff --git a/dev-requirements.txt b/dev-requirements.txt
index 01030e8..752517d 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -1,5 +1,6 @@
 flake8
 pretend
-pytest-cov
+pytest
+coverage
 sphinx
 tox