[requires.io] dependency update

requires · requires · commit f0141587d82b · 2017-08-09T10:46:40.000-05:00
diff --git a/test_requirements.txt b/test_requirements.txt
@@ -1,4 +1,4 @@
 pytest==3.2.0
 pytest-cov==2.5.1
-pytest-xdist==1.18.2
+pytest-xdist==1.19.0
 hypothesis==3.17.0
