fix parsing bug

parser.cpp

@@ -427,7 +427,8 @@ namespace usql {
 
 	    // parenthised expression
 	    if (token_type == TokenType::open_paren) {
-		    // open paren already consumed
+            m_lexer.skipToken(TokenType::open_paren);
+            
 		    auto left = parse_expression();
 		    do {
 			left = parse_expression(std::move(left));