Update @vue/compat to at least 3.4.27

What

We need to update @vue/compat to at least 3.4.27

Why

The newer compat version includes a fix to better handle the copying of the default slot for $scopedSlots which is the preferred way to handle slots for the Vue 3 migration. It was discussed at length here and will effectively fix Dropdowns: Icons are smaller in Vue 3 (#2901 - closed) because of it.