Trailing and leading spaces are not trimmed in widget configuration form input fields

Problem description: Trailing and leading spaces are not trimmed in input elements in widget configuration form. This seams strange, as in all other views trailing and leading spaces are removed from input elements.

Steps to reproduce:

1. Open any existing Dashboard in edit mode
2. Press "Add widget"
3. In the opened configuration form type a value in field Name with trailing and leading spaces
4. Save the widget
5. Open configuration of the saved widget

Result: Trailing and leading spaces are still present in the name of the widget. This also applies to other input elements in widget configuration form
Expected: trailing and leading spaces should be trimmed, same as in other frontend views.