2.9: Buttons Radio without explicit group example
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**Primary Actor**: User

**Scope**: Ngx-bootstrap DEMO / BS version 3&4

**Goal**: Show user radio without explicit group example

Main success scenario:
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1. User opens Buttons demo page
2. User clicks on Radio without explicit group sub-menu
3. User sees button-group, containing 3 clickable buttons named "Left", "Middle" and "Right", with the custom checkbox value field under it. 
4. By default, 1st button is inactive, 2d - active, and 3d - inactive, and the text: "Middle" displayed in the custom checkbox value field.
5. User able to click on each button
6. When user clicks on the inactive button, it becomes active and other buttons become inactive, and this button name is displayed in the custom checkbox value field
7. When user press on tab key to switch on the next button, it button become touched but the previous button is still active and its name is displayed in the custom checkbox value field
9. When user presses the space key after that, the touched button becomes active and its name is displayed in the custom checkbox value

Variations:
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2*. User scrolls to Radio without explicit group sub-menu