fix(buttons): fix button unit test onclic input event

Created by: Lausselloic

fix one unit test down due to onclic event

Don't remove the latest unit test failing :

  QUnit.test('should toggle aria-pressed on buttons with container', function (assert) {
    assert.expect(1)
    var groupHTML = '<div class="btn-group" data-toggle="buttons">' +
        '<button id="btn1" class="btn btn-secondary" type="button">One</button>' +
        '<button class="btn btn-secondary" type="button">Two</button>' +
      '</div>'
    $('#qunit-fixture').append(groupHTML)
    $('#btn1').bootstrapButton('toggle')
    assert.strictEqual($('#btn1').attr('aria-pressed'), 'true')
  })

Not sure if that structure need to be available? If yes need to fix the plugin, if no need to remove the test