Scheduled weekly dependency update for week 52

[pyup-bot]

Updates

Here's a list of all the updates bundled in this pull request. I've added some links to make it easier for you to find all the information you need.

asn1crypto	0.23.0	»	0.24.0	PyPI | Changelog | Repo
ipaddress	1.0.18	»	1.0.19	PyPI | Repo

Changelogs

asn1crypto 0.23.0 -> 0.24.0

0.24.0

• x509.Certificate().self_signed will no longer return "yes" under any
  circumstances. This helps prevent confusion since the library does not
  verify the signature. Instead a library like oscrypto should be used
  to confirm if a certificate is self-signed.
• Added various OIDs to x509.KeyPurposeId()
• Added x509.Certificate().private_key_usage_period_value
• Added structures for parsing common subject directory attributes for
  X.509 certificates, including x509.SubjectDirectoryAttribute()
• Added algos.AnyAlgorithmIdentifier() for situations where an
  algorithm identifier may contain a digest, signed digest or encryption
  algorithm OID
• Fixed a bug with x509.Certificate().subject_directory_attributes_value
  not returning the correct value
• Fixed a bug where explicitly-tagged fields in a core.Sequence() would
  not function properly when the field had a default value
• Fixed a bug with type checking in pem.armor()

That's it for now!

Happy merging! 🤖

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This change is 

[pyup-bot]

Closing this in favor of #124