created a test for the new error that should be thrown if an invalid character is in the key for XOR with a Hex option

src/core/operations/XOR.mjs

@@ -46,7 +46,7 @@ class XOR extends Operation {
             {
                 "name": "Filter Key",
                 "type": "boolean",
-                "value": true
+                "value": false
             }
         ];
     }