fix(deps): Remove domain-validator dependency

It is broken in multiple ways

chatmaild/pyproject.toml

@@ -10,7 +10,6 @@ dependencies = [
   "filelock",
   "requests",
   "crypt-r >= 3.13.1 ; python_version >= '3.11'",
-  "domain-validator",
 ]
 
 [tool.setuptools]

chatmaild/src/chatmaild/config.py

@@ -2,7 +2,6 @@ import ipaddress
 from pathlib import Path
 
 import iniconfig
-from domain_validator import DomainValidator
 
 from chatmaild.user import User
 
@@ -25,7 +24,6 @@ class Config:
             self.mail_domain = f"[{raw_domain}]"
             self.postfix_myhostname = ipaddress.IPv4Address(raw_domain).reverse_pointer
         else:
-            DomainValidator().validate_domain_re(raw_domain)
             self.ipv4_relay = None
             self.mail_domain = raw_domain
             self.postfix_myhostname = raw_domain

cmdeploy/src/cmdeploy/tests/plugin.py

@@ -10,13 +10,11 @@ from pathlib import Path
 
 import pytest
 from chatmaild.config import is_valid_ipv4, read_config
-from domain_validator import DomainValidator
 
 
 def format_mail_domain(raw_domain: str) -> str:
     if is_valid_ipv4(raw_domain):
         return f"[{raw_domain}]"
-    DomainValidator().validate_domain_re(raw_domain)
     return raw_domain