Merge pull request #2694 from docker/dependabot/pip/cryptography-3.2

Bump cryptography from 2.3 to 3.2

Author: aiordache

requirements.txt

@@ -2,7 +2,7 @@ appdirs==1.4.3
 asn1crypto==0.22.0
 backports.ssl-match-hostname==3.5.0.1
 cffi==1.10.0
-cryptography==2.3
+cryptography==3.2
 enum34==1.1.6
 idna==2.5
 ipaddress==1.0.18