Bump cryptography from 3.3.2 to 3.4.5

Bumps [cryptography](https://github.com/pyca/cryptography) from 3.3.2 to 3.4.5.
- [Release notes](https://github.com/pyca/cryptography/releases)
- [Changelog](https://github.com/pyca/cryptography/blob/main/CHANGELOG.rst)
- [Commits](https://github.com/pyca/cryptography/compare/3.3.2...3.4.5)

Signed-off-by: dependabot[bot] <support@github.com>

requirements.txt

@@ -3,7 +3,7 @@ pandas==1.2.2
 
 ccxt==1.41.90
 # Pin cryptography for now due to rust build errors with piwheels
-cryptography==3.3.2
+cryptography==3.4.5
 aiohttp==3.7.3
 SQLAlchemy==1.3.23
 python-telegram-bot==13.2