Fix dropdown overflow for enums (#8668)

packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_view.dart

diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_view.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_view.dart
index 832c736..684bfbc 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_view.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_view.dart
@@ -175,6 +175,7 @@
                   child: Text(option),
                 );
               }).toList(),
+          isExpanded: true,
           onChanged: (newValue) async {
             await _editArgument(newValue);
           },