Introduce prefix-text and suffix-text properties

[juuso-vaadin]

Describe your motivation

For developer's convenience there could be configurable properties for prefix-text and suffix-text in all input components. Currently the helper-text is handled with a property, but prefix/suffix require referring to a slot.

This should only add to current functionality which means that adding components to the slots would have to be done the same way as before.

Describe the solution you'd like

Text property

<vaadin-text-field
  label="Amount"
  helper-text="Including VAT"
  suffix-text="USD">

in addition to referring to a slot

<vaadin-text-field
  label="Amount"
  helper-text="Including VAT"
  <span slot="suffix">USD</span>>

Describe alternatives you've considered

No response

Additional context

No response