Resolve spurious blueprint panel group collapsing (#4548)

### What
 - Resolves: #4453

Needed to make the id deterministic since the value of DataResultHandle
was basically just a function of how many children the data-result had.

### Checklist
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* Using newly built examples:
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[app.rerun.io](https://app.rerun.io/pr/4548/index.html?manifest_url=https://app.rerun.io/version/main/examples_manifest.json)
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usefulness for the next release's CHANGELOG

- [PR Build Summary](https://build.rerun.io/pr/4548)
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crates/re_viewport/src/viewport_blueprint_ui.rs

@@ -358,16 +358,21 @@ impl ViewportBlueprint<'_> {
 
                         response | vis_response
                     })
-                    .show_collapsing(ui, ui.id().with(child), default_open, |_, ui| {
-                        Self::space_view_blueprint_ui(
-                            ctx,
-                            ui,
-                            query_result,
-                            *child,
-                            space_view,
-                            space_view_visible,
-                        );
-                    })
+                    .show_collapsing(
+                        ui,
+                        ui.id().with(&child_node.data_result.entity_path),
+                        default_open,
+                        |_, ui| {
+                            Self::space_view_blueprint_ui(
+                                ctx,
+                                ui,
+                                query_result,
+                                *child,
+                                space_view,
+                                space_view_visible,
+                            );
+                        },
+                    )
                     .item_response
                     .on_hover_ui(|ui| {
                         if data_result.is_group {