fixup! Introduction of the fc2.com SPECIAL rule.

This patch fixes #271.
This patch touches #269.

Contributors:
  * @spirillen
  * @T145

Author: funilrys

PyFunceble/checker/availability/extra_rules.py

@@ -310,7 +310,7 @@ def __handle_fc2_dot_com(self) -> "ExtraRulesHandler":
 
         req = PyFunceble.factory.Requester.get(url, allow_redirects=False)
 
-        if "error.fc2.com" in req.headers["Location"]:
+        if "Location" in req.headers and "error.fc2.com" in req.headers["Location"]:
             self.__switch_to_down()
 
         return self