Update cryptography dependency (#630)

### Changes

This PR updates the requirements.txt file to update cryptography to
41.0.5

Please describe both what is changing and why this is important.
Include:

- Endpoints added, deleted, deprecated, or changed
- Classes and methods added, deleted, deprecated, or changed
- Screenshots of new or changed UI, if applicable
- A summary of usage if this is a new feature or change to a public API
(this should also be added to relevant documentation once released)
- Any alternative designs or approaches considered

### References


Closes #627

Please include relevant links supporting this change such as a:

- support ticket
- community post
- StackOverflow post
- support forum thread

### Testing

Please describe how this can be tested by reviewers. Be specific about
anything not tested and reasons why. If this library has unit and/or
integration testing, tests should be added for new functionality and
existing tests should complete without errors.

- [ ] This change adds unit test coverage
- [ ] This change adds integration test coverage
- [ ] This change has been tested on the latest version of the
platform/language or why not

### Checklist

- [ ] I have read the [Auth0 general contribution
guidelines](https://github.com/auth0/open-source-template/blob/master/GENERAL-CONTRIBUTING.md)
- [ ] I have read the [Auth0 Code of
Conduct](https://github.com/auth0/open-source-template/blob/master/CODE-OF-CONDUCT.md)
- [ ] All existing and new tests complete without errors