Bump cryptography from 2.9.2 to 3.1 in /backend

[dependabot]

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Bumps cryptography from 2.9.2 to 3.1.

Changelog

Sourced from cryptography's changelog.

3.1 - 2020-08-26

* **BACKWARDS INCOMPATIBLE:** Removed support for ``idna`` based
  :term:`U-label` parsing in various X.509 classes. This support was originally
  deprecated in version 2.1 and moved to an extra in 2.5.
* Deprecated OpenSSL 1.0.2 support. OpenSSL 1.0.2 is no longer supported by
  the OpenSSL project. The next version of ``cryptography`` will drop support
  for it.
* Deprecated support for Python 3.5. This version sees very little use and will
  be removed in the next release.
* ``backend`` arguments to functions are no longer required and the
  default backend will automatically be selected if no ``backend`` is provided.
* Added initial support for parsing certificates from PKCS7 files with
  :func:`~cryptography.hazmat.primitives.serialization.pkcs7.load_pem_pkcs7_certificates`
  and
  :func:`~cryptography.hazmat.primitives.serialization.pkcs7.load_der_pkcs7_certificates`
  .
* Calling ``update`` or ``update_into`` on
  :class:`~cryptography.hazmat.primitives.ciphers.CipherContext` with ``data``
  longer than 2\ :sup:`31` bytes no longer raises an ``OverflowError``. This
  also resolves the same issue in :doc:`/fernet`.
.. _v3-0:
3.0 - 2020-07-20

• BACKWARDS INCOMPATIBLE: Removed support for passing an :class:~cryptography.x509.Extension instance to :meth:~cryptography.x509.AuthorityKeyIdentifier.from_issuer_subject_key_identifier, as per our deprecation policy.

• BACKWARDS INCOMPATIBLE: Support for LibreSSL 2.7.x, 2.8.x, and 2.9.0 has been removed (2.9.1+ is still supported).

• BACKWARDS INCOMPATIBLE: Dropped support for macOS 10.9, macOS users must upgrade to 10.10 or newer.

• BACKWARDS INCOMPATIBLE: RSA :meth:~cryptography.hazmat.primitives.asymmetric.rsa.generate_private_key no longer accepts public_exponent values except 65537 and 3 (the latter for legacy purposes).

• BACKWARDS INCOMPATIBLE: X.509 certificate parsing now enforces that the version field contains a valid value, rather than deferring this check until :attr:~cryptography.x509.Certificate.version is accessed.

• Deprecated support for Python 2. At the time there is no time table for actually dropping support, however we strongly encourage all users to upgrade their Python, as Python 2 no longer receives support from the Python core team.

  If you have trouble suppressing this warning in tests view the :ref:FAQ entry addressing this issue <faq-howto-handle-deprecation-warning>.

Commits

• ba2c0e5 3.1 release (#5430)
• c63106c Build manylinux wheels with Zuul (#5386)
• bda1387 new black, actually slightly different than the old black (#5429)
• 0b24359 remove keywords with side effects hack in setup.py (#5426)
• 1394edb rephrase changelog entry (#5422)
• b9d26d2 add some words about separating ECDH and ECDSA (#5423)
• ed3ded4 bump libressl 3.1.x (#5421)
• b6c51be document that we auto-chunk on symmetric cipher contexts now (#5420)
• f90ba18 chunked update_into (#5419)
• bc4b956 Run AWS SDK tests on Python 3.7 (#5414)
• Additional commits viewable in compare view

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[Seluj78]

@dependabot merge