Use same styling for spaces between icon and file name

This is only visible when selecting both icon and file name, as most terminal emulators then invert background and foreground color.

It also workaround a Konsole bug: https://bugs.kde.org/show_bug.cgi?id=422776

src/output/file_name.rs

@@ -132,9 +132,9 @@ impl<'a, 'dir, C: Colours> FileName<'a, 'dir, C> {
             bits.push(style.paint(file_icon));
 
             match spaces_count {
-                1 => bits.push(Style::default().paint(" ")),
-                2 => bits.push(Style::default().paint("  ")),
-                n => bits.push(Style::default().paint(spaces(n))),
+                1 => bits.push(style.paint(" ")),
+                2 => bits.push(style.paint("  ")),
+                n => bits.push(style.paint(spaces(n))),
             }
         }