Bump dnspython from 2.2.0 to 2.2.1 (#1679)

* Bump dnspython from 2.2.0 to 2.2.1

Bumps [dnspython](https://github.com/rthalley/dnspython) from 2.2.0 to 2.2.1.
- [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/v2.2.0...v2.2.1)

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

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

* Update dnspython==2.2.1

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/tokenizer.py

@@ -600,9 +600,12 @@ class Tokenizer:
                 break
         return tokens
 
-    def concatenate_remaining_identifiers(self):
+    def concatenate_remaining_identifiers(self, allow_empty=False):
         """Read the remaining tokens on the line, which should be identifiers.
 
+        Raises dns.exception.SyntaxError if there are no remaining tokens,
+        unless `allow_empty=True` is given.
+
         Raises dns.exception.SyntaxError if a token is seen that is not an
         identifier.
 
@@ -618,6 +621,8 @@ class Tokenizer:
             if not token.is_identifier():
                 raise dns.exception.SyntaxError
             s += token.value
+        if not (allow_empty or s):
+            raise dns.exception.SyntaxError('expecting another identifier')
         return s
 
     def as_name(self, token, origin=None, relativize=False, relativize_to=None):