Fix: Make explicit/implicit returns consistent

The check_command_status function will now always explicitly return
False unless the check succeeds while the non-None return from
_ssh_authentication_input_loop has been removed.

gvm/connections.py

@@ -313,7 +313,7 @@ def _ssh_authentication_input_loop(
                         save = input()
                 break
             elif add == "no":
-                return sys.exit(
+                sys.exit(
                     "User denied key. Host key verification failed."
                 )
             else:

gvm/utils.py

@@ -66,10 +66,13 @@ def check_command_status(xml: str) -> bool:
     except KeyError:
         print(logger)
         logger.error("Not received an status code within the response.")
+        return False
     except etree.Error as e:
         logger.error("etree.XML(xml): %s", e)
         return False
 
+    return False
+
 
 def to_dotted_types_dict(types: List) -> TypesDict:
     """Create a dictionary accessible via dot notation"""