ngbButton type="checkbox" does not get unchecked after click

[pellyadolfo]

Issue type

I'm submitting a ... (check one with "x")

• bug report
• feature request
• question about the decisions made in the repository

Issue description

Current behavior:
Click on checked checkbox does not uncheck. I need to click in other component in order the checkbox repaints

Expected behavior:
Should automatically show as unchecked after click

Steps to reproduce:
In ngx-admin -> UI Features -> buttons -> button groups -> Divided Button Group -> second row -> click middle e.g. -> middle gets checked -> click again middle -> nothing happens -> click anywhere else -> middle gets unchecked

[nnixaa]

Thanks @pellyadolfo for reporting!