python: cve: use latest cryptography and urllib3

Change-Id: I4c1994ab7dc27f902aa51ac6945776c23f9ff2fd
Signed-off-by: Adrian Vladu <[email protected]>

Author: ader1990

tox.ini

@@ -7,7 +7,7 @@ skipsdist = True
 usedevelop = True
 setenv = VIRTUAL_ENV={envdir}
 deps =
-  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://raw.githubusercontent.com/ader1990/requirements/6b1f4edc570f147822ddc3e5469c0e01c4b60be0/upper-constraints.txt}
   -r{toxinidir}/test-requirements.txt
   -r{toxinidir}/requirements.txt
 commands = stestr run --slowest {posargs}