Handle query dns timeout unhandled error (#1950)

Co-authored-by: hala alajlan <halalajlan@gmail.com>

management/status_checks.py

@@ -664,6 +664,8 @@ def check_mail_domain(domain, env, output):
 
 	if mx is None:
 		mxhost = None
+	elif mx == "[timeout]":
+        mxhost = None
 	else:
 		# query_dns returns a semicolon-delimited list
 		# of priority-host pairs.