Set the correct dispatch action for the double-click handler for the pane tab bar (#9221)

Fixes #9003

Release Notes:

- Fixed the double-click action on the terminal tab bar opening a new
buffer instead of a new terminal
([#9003](https://github.com/zed-industries/zed/issues/9003)).

crates/workspace/src/workspace.rs

@@ -618,6 +618,7 @@ impl Workspace {
                 project.clone(),
                 pane_history_timestamp.clone(),
                 None,
+                NewFile.boxed_clone(),
                 cx,
             )
         });
@@ -1860,6 +1861,7 @@ impl Workspace {
                 self.project.clone(),
                 self.pane_history_timestamp.clone(),
                 None,
+                NewFile.boxed_clone(),
                 cx,
             )
         });