Fix error in mapping generator

The error occured when you try to add an "Include names" filter

recaf-ui/src/main/java/software/coley/recaf/ui/pane/MappingGeneratorPane.java

@@ -789,7 +789,7 @@ protected void fillConfigurator(@Nonnull BiConsumer<StringBinding, Node> sink) {
 			grid.addRow(2, new BoundLabel(Lang.getBinding("mapgen.filter.method-name")),
 					txtMethod, new BoundComboBox<>(methodPredicateId, stringPredicatesWithNull, textPredicateConverter));
 			grid.addRow(3, new BoundLabel(Lang.getBinding("mapgen.filter.variable-name")),
-					txtMethod, new BoundComboBox<>(variablePredicateId, stringPredicatesWithNull, textPredicateConverter));
+					txtVariable, new BoundComboBox<>(variablePredicateId, stringPredicatesWithNull, textPredicateConverter));
 			sink.accept(null, grid);
 		}
 	}