Update cryptography python module.

https://github.com/ElementsProject/lightning/blob/ca80dee5145ff9240aa6b4e342e14332bec9973b/contrib/pyln-proto/pyproject.toml#L18

this version of cryptography has a high severity issue as seen here:
https://github.com/lnbits/lnbits/security/dependabot/18

is it possible to update this?