Remove pypy job

Pypy is not tested in OpenStack anymore, remove the job.

Change-Id: I747f30a385b8163ac1ea173b0a8024c281fc272b

tox.ini

@@ -1,7 +1,7 @@
 [tox]
 minversion = 3.1
 skipsdist = True
-envlist = pep8,py37,pypy
+envlist = pep8,py37
 ignore_basepython_conflict = True
 
 [testenv]
@@ -27,9 +27,6 @@ basepython = python3.6
 [testenv:py37]
 basepython = python3.7
 
-[testenv:pypy]
-basepython = pypy
-
 [testenv:debug]
 commands = oslo_debug_helper -t kolla/tests {posargs}