[requires.io] dependency update

requires · requires · commit 1524070dd51d · 2017-08-17T18:30:21.000-05:00
diff --git a/test_requirements.txt b/test_requirements.txt
@@ -1,3 +1,3 @@
 pytest==3.2.1
 pytest-cov==2.5.1
-hypothesis==3.18.3
+hypothesis==3.18.4
