Merge pull request #2339 from ulyssessouza/bump-urllib3

Bump urllib3 -> 1.24.3

Author: shin-

requirements.txt

@@ -15,5 +15,5 @@ pypiwin32==219; sys_platform == 'win32' and python_version < '3.6'
 pypiwin32==223; sys_platform == 'win32' and python_version >= '3.6'
 requests==2.20.0
 six==1.10.0
-urllib3==1.24.1
+urllib3==1.24.3
 websocket-client==0.40.0