[requires.io] dependency update

Author: requires

tox.ini

@@ -56,7 +56,7 @@ deps =
 
     # For code coverage
     {[testenv:coverage_report]deps}
-    pytest-cov==2.9.0
+    pytest-cov==2.10.0
 
     # For hypothesis. Note Python 3.4 isn't supported by hypothesis.
     py27: hypothesis==4.43.9