Fix superfluous `"` in error message

modules/gdscript/gdscript_parser.cpp

@@ -2446,7 +2446,7 @@ GDScriptParser::ExpressionNode *GDScriptParser::parse_binary_operator(Expression
 	complete_extents(operation);
 
 	if (operation->right_operand == nullptr) {
-		push_error(vformat(R"(Expected expression after "%s" operator.")", op.get_name()));
+		push_error(vformat(R"(Expected expression after "%s" operator.)", op.get_name()));
 	}
 
 	// TODO: Also for unary, ternary, and assignment.