Add support for cryptography CRLs to X509Store

[facutuesca]

As a follow up to deprecating CRL APIs (#1249), there is one remaining function that won't be deprecated but accepts the CRL type: X509Store.add_crl(crl: CRL). In order to give users an alternative once CRL is deprecated, this PR adds support to add_crl() so that it also accepts cryptography's X509.CertificateRevocationList.

This PR also adds tests for the new code path, by parametrizing existing tests that use add_crl so that the CRL being passed as a parameter is either PyOpenSSL's or cryptography's. For example:

    @pytest.mark.parametrize(
        "create_crl",
        [
            pytest.param(
                _make_test_crl,
                id="pyOpenSSL CRL",
            ),
            pytest.param(
                _make_test_crl_cryptography,
                id="cryptography CRL",
            ),
        ],
    )
    def test_verify_with_revoked(self, create_crl):
            #...
            root_crl = create_crl(self.root_cert, self.root_key, certs=[self.intermediate_cert])
            #...

[reaperhulk]

Did this fail mypy or are we avoiding deprecation warnings?

[facutuesca]

It's for the docs, see the current type signature for this function:

add_revoked(revoked: <cryptography.utils._DeprecatedValue object at 0x7f66c71ab1d0>) → None
Add a revoked (by value not reference) to the CRL structure

[reaperhulk]

This still needs a changelog entry 😄

[facutuesca]

This still needs a changelog entry 😄

@reaperhulk My bad, fixed!