Open folds containing selections when jumping from multibuffer (#21433)

When searching within a single buffer, activating a search result causes
any fold containing the result to be unfolded. However, this didn't
happen when jumping to a search result from a project-wide search
multibuffer. This PR fixes that.

Release Notes:

- Fixed folds not opening when jumping from search results multibuffer

crates/editor/src/editor.rs

@@ -12876,6 +12876,7 @@ impl Editor {
                             None => Autoscroll::newest(),
                         };
                         let nav_history = editor.nav_history.take();
+                        editor.unfold_ranges(&ranges, false, true, cx);
                         editor.change_selections(Some(autoscroll), cx, |s| {
                             s.select_ranges(ranges);
                         });