cloud-tests: update cryptography requirement

[powersj]

Proposed Commit Message

cloud-tests: update cryptography requirement

Test Steps

I ran a few cloud tests like:

tox -e citest -- run --os-name focal -t modules/bootcmd

And ensured the test passed and the correct version, 3.2, of cryptography was pulled in.

Checklist:

• My code follows the process laid out in the documentation
• I have updated or added any unit tests accordingly
• I have updated or added any documentation accordingly

[OddBloke]

Thanks!