Fix style overwriting in table rows with multiple cells

This is a fix for a subtle bug in the styling of cells in a table:
only the last Cell in the selected Row will display fuzzy-matching
highlights.

The simplest way to reproduce the bug is to open up the buffer picker.
Inputting a buffer ID number or a flag which is present like * should
highlight matched characters with your theme's 'ui.text.focus' scope,
but the styles are not applied.

The issue is that the block moved in this commit was called per-cell
but operates on the whole row's area. The block must be moved outside
the for-loop over the cells.

helix-tui/src/widgets/table.rs

@@ -450,11 +450,11 @@ impl<'a> Table<'a> {
             } else {
                 col
             };
+            if is_selected {
+                buf.set_style(table_row_area, self.highlight_style);
+            }
             let mut col = table_row_start_col;
             for (width, cell) in columns_widths.iter().zip(table_row.cells.iter()) {
-                if is_selected {
-                    buf.set_style(table_row_area, self.highlight_style);
-                }
                 render_cell(
                     buf,
                     cell,