cryptography module 40.0.0 removed needed function, pinning to lower version (#254)

Author: mmaeng

src/setup.py

@@ -16,6 +16,7 @@
     install_requires=[
         "boto3>=1.10.20",
         "aws-encryption-sdk==3.1.0",
+        "cryptography<40.0.0",
         'dataclasses;python_version<"3.7"',
     ],
     license="Apache License 2.0",