project panel: Fix preview tabs not working when enabled (#20416)

PR #20154 introduced a regression and essentially disabled preview tabs
in code.

This fixes it and restores the old preview tabs behavior.

Release Notes:

- Fixed preview tabs being disabled in code, even if they were enabled
in the settings.

Co-authored-by: Piotr <piotr@zed.dev>

crates/project_panel/src/project_panel.rs

@@ -2665,7 +2665,7 @@ impl ProjectPanel {
                             entry_id,
                             cx.modifiers().secondary(),
                             !preview_tabs_enabled || click_count > 1,
-                            !preview_tabs_enabled && click_count == 1,
+                            preview_tabs_enabled && click_count == 1,
                             cx,
                         );
                     }