Fix string index bug in table repr (#1079)

Co-authored-by: Xiayue Charles Lin <[email protected]>

src/table/mod.rs

@@ -509,7 +509,7 @@ impl Table {
                 .map(|s| {
                     let mut str_val = s.str_value(i).unwrap();
                     if let Some(max_col_width) = max_col_width {
-                        if s.len() > max_col_width {
+                        if str_val.len() > max_col_width {
                             str_val = format!("{}...", &str_val[..max_col_width - 3]);
                         }
                     }