🐛 [CommandBar] Tooltip not shown in secondary items

**Describe the bug**
The `CommandBar` let us add `CommandBarItems` as primary or secondary. The `CommandBarButton` has a `tooltip` field, but if the item is shown as secondary the tooltip will not be shown.

**To Reproduce**
An example:
```dart
PageHeader(
title: Text('Operations'),
commandBar: CommandBar(
mainAxisAlignment: MainAxisAlignment.end,
primaryItems: [
CommandBarButton(
onPressed: () {},
label: Text("Add an operation"),
icon: const Icon(FluentIcons.add_to_shopping_list),
tooltip: "Add a new operation", // This is shown on mouseover
),
],
secondaryItems: [
CommandBarButton(
onPressed: (){},
label: Text("Export operations"),
icon: const Icon(FluentIcons.export),
tooltip: 'export_all_your_operations_in_an_excel_file', // This is not shown
),
],
),
),
```

**Expected behavior**
The tooltip should be displayed in the secondary items menu too. A workaround for me actually is this:
```dart
CommandBarButton(
onPressed: (){},
label: Tooltip(
message:
'export_all_your_operations_in_an_excel_file',
child: Text("Export operations")),
icon: const Icon(FluentIcons.export),
),
```

**Additional context**
-

Start by tracing the CommandBar and CommandBarButton implementations, comparing how tooltips are handled for primary items with how secondary items are rendered. Reproduce the provided example and verify that the secondary menu displays the button tooltip without requiring the workaround.

Written by the indexing model from the issue text.