Update cryptography from 2.8 to 42.0.3

requirements_dev.txt

@@ -1,6 +1,6 @@
 bump2version==0.5.11
 coverage==4.5.4
-cryptography==2.8
+cryptography==42.0.3
 flake8==3.7.8
 pip==19.3.1
 pytest==5.2.2