Remove pypy from default envlist

TrivialFix

Change-Id: I75b0d2c1a07a407e7bae4fdc14928adfc46156de
diff --git a/tox.ini b/tox.ini
index 454b8df..907516f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,6 @@
 [tox]
 minversion = 3.1.1
-envlist = py3,pypy,pep8
+envlist = py3,pep8
 
 [testenv]
 basepython = python3