Bump dnspython from 2.2.1 to 2.3.0 (#1975)

* Bump dnspython from 2.2.1 to 2.3.0

Bumps [dnspython](https://github.com/rthalley/dnspython) from 2.2.1 to 2.3.0.
- [Release notes](https://github.com/rthalley/dnspython/releases)
- [Changelog](https://github.com/rthalley/dnspython/blob/master/doc/whatsnew.rst)
- [Commits](https://github.com/rthalley/dnspython/compare/v2.2.1...v2.3.0)

---
updated-dependencies:
- dependency-name: dnspython
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

* Update dnspython==2.3.0

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: JonnyWong16 <9099342+JonnyWong16@users.noreply.github.com>

[skip ci]

lib/dns/zonetypes.py

@@ -0,0 +1,37 @@
+# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
+
+"""Common zone-related types."""
+
+# This is a separate file to avoid import circularity between dns.zone and
+# the implementation of the ZONEMD type.
+
+import hashlib
+
+import dns.enum
+
+
+class DigestScheme(dns.enum.IntEnum):
+    """ZONEMD Scheme"""
+
+    SIMPLE = 1
+
+    @classmethod
+    def _maximum(cls):
+        return 255
+
+
+class DigestHashAlgorithm(dns.enum.IntEnum):
+    """ZONEMD Hash Algorithm"""
+
+    SHA384 = 1
+    SHA512 = 2
+
+    @classmethod
+    def _maximum(cls):
+        return 255
+
+
+_digest_hashers = {
+    DigestHashAlgorithm.SHA384: hashlib.sha384,
+    DigestHashAlgorithm.SHA512: hashlib.sha512,
+}