selectInput(selectize=FALSE) requires a `form-select` class

This might belong in the shiny repo. When creating a selectInput() with `selectize=FALSE` in bootstrap 5, the resulting input does not have a chevron arrow on the side that makes it clear this is an openable box. See screenshot. This makes it appear as a text input. The input needs to add `class="form-select"` to appear correctly in bs5. <img width="314" height="83" alt="Image" src="https://github.com/user-attachments/assets/eba1c3dd-9e9e-4a3d-9410-5db9d4da4e1b" />