0.4: Accordion disabled panels example
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**Primary Actor**: User

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

**Goal**: Show how to disable/enable accordion items

Main success scenario:
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1. User open Accordion demo page
2. User click on Disabled sub-menu
3. User able to click on each item of 3
4. When user click on "Enable/Disable first panel" button then the first item is not clickable
5. When user click on "Enable/Disable first panel" second time and click on first item, then item opened and user see content
6. When user click on "Enable/Disable first panel" third time then the first item is not clickable again

Variations:
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2*. User scroll to Disabled sub-menu