Fix: Fixes broken installation because of third party library update.

Change-Id: If94adb111ae5bf89f977ad857807f89ee61f71d8
Signed-off-by: peusterm <manuel.peuster@uni-paderborn.de>
diff --git a/setup.py b/setup.py
index 090063a..7cc9d6b 100755
--- a/setup.py
+++ b/setup.py
@@ -51,7 +51,7 @@
           'Flask',
           'flask_restful',
           'docker==2.0.2',
-          'urllib3==1.21.1',
+          'urllib3',
           'requests',
           'prometheus_client',
           'ipaddress',