Allow to choose another field to define the wrapper tag

applied patch to D11, it seems to work, but it's very unintuitive how to use it.
maybe add description to "Field wrapper - Other field" what kind of field it should be, eg "list_string field and should be validated that its a valid html tag."

also, maybe it should be a separate field formatter which extends TextFieldFormatter not to add too much complexity and clutter to the code ?

#[FieldFormatter(
  id: 'text_field_wrap_formatter',
  label: new TranslatableMarkup('Text field formatter with wrap field'),
  field_types: [
    'string',
  ],
)]
class TextFieldWrapFormatter extends TextFieldFormatter {
...
}

(MR8 doubles complexity of the code).