UX improvements for AsyncSelectInput and SearchSelectInput when iconLeft is given

[LucasGrahn]

Describe the bug

The icon from the iconLeft property disappears after typing.

Also when I click into those components the cursor is at the end of the placeholder.

Expected behavior

The icon defined inside the iconLeft property should be shown when I type.
When I click into those inputs the cursor should start next to the icon when the placeholder is shown.

Screenshots

Additional context

Affected components: SearchSelectInput and AsyncSelectInput