Bump cryptography from 2.9.2 to 3.0

Bumps [cryptography](https://github.com/pyca/cryptography) from 2.9.2 to 3.0.
- [Release notes](https://github.com/pyca/cryptography/releases)
- [Changelog](https://github.com/pyca/cryptography/blob/master/CHANGELOG.rst)
- [Commits](pyca/cryptography@2.9.2...3.0)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

requirements.txt

@@ -5,7 +5,7 @@ boto3==1.14.24
 celery==4.4.6
 celery-batches==0.3
 # For Azure Tenant auth
-cryptography==2.9.2
+cryptography==3.0
 defusedxml==0.6.0
 Django==3.0.8
 django-appconf==1.0.4