<li class="list-item">
    <span class="email">{{$ctrl.user.email}}</span>
    <span ng-if="($ctrl.user.admin === true)"><i class="icon ion-android-star warning"></i></span>
    <div class="list-item__edge edge--right">
        <div class="button-group at-right">
            <button
                ng-repeat="btn in $ctrl.buttons"
                ng-if="btn.show($ctrl.user)"
                class="{{btn.class}}"
                ng-click="btn.action($ctrl.user)">
                {{btn.text}}
            </button>
            <button class="btn--clear" ng-click="$ctrl.openRemoveModal()"><i class="icon ion-android-close"></i></button>
        </div>
    </div>
</li>

<li class="list-item">
    <span class="email">{{$ctrl.user.email}}</span>
    <span ng-if="($ctrl.user.admin === true)"><i class="icon ion-android-star warning"></i></span>
    <div class="list-item__edge edge--right">
        <button
            ng-repeat="btn in $ctrl.buttons"
            ng-if="btn.show($ctrl.user)"
            class="{{btn.class}}"
            ng-click="btn.action($ctrl.user)">
            {{btn.text}}
        </button>
        <button class="btn--clear" ng-click="$ctrl.openRemoveModal()"><span class="icon icon--dark">&times;</span></button>
    </div>
</li>

Remove button group markup, use times html code for remove button
Remove button group markup, use times html code for remove button
