fixed comment

deep_translator/microsoft.py

@@ -44,7 +44,7 @@ class MicrosoftTranslator(BaseTranslator):
             "Ocp-Apim-Subscription-Key": self.api_key,
             "Content-type": "application/json",
         }
-        # region is not required but very common and goes to headers if passed
+        # parameter region is not required but very common and goes to headers if passed
         if region:
             self.region = region
             self.headers["Ocp-Apim-Subscription-Region"] = self.region