refactor: do not $compile sidebar btn

Use HsSidebarService.buttons instead of AngularJS' element & $compile

src/app.component.js

@@ -28,8 +28,15 @@ export const HsComponent = {
     HsLayoutService.sidebarRight = false;
     // HsLayoutService.sidebarToggleable = false;
     // HsCore.singleDatasources = true;
-    HsLayoutService.sidebarButtons = true;
-    HsLayoutService.setDefaultPanel('adjuster');
+    //HsLayoutService.sidebarButtons = true;
+    HsSidebarService.buttons.push({
+      panel: 'adjuster',
+      module: 'pra.adjuster',
+      order: '6',
+      title: 'Adjust factors',
+      description: '',
+      icon: 'icon-analytics-piechart',
+    });
     $scope.$on('scope_loaded', function (event, args) {
       if (args === 'Sidebar') {
         const el = angular.element(
@@ -37,11 +44,7 @@ export const HsComponent = {
         )[0];
         HsLayoutService.panelListElement.appendChild(el);
         $compile(el)($scope);
-        const toolbarButton = angular.element(
-          '<pra-adjuster-sidebar-btn></pra-adjuster-sidebar-btn>'
-        )[0];
-        HsLayoutService.sidebarListElement.appendChild(toolbarButton);
-        $compile(toolbarButton)(event.targetScope);
+        HsLayoutService.setDefaultPanel('adjuster');
         const loader = angular.element(
           '<pra-adjuster-loader class="loader-splash" ng-if="vm.PraAdjusterService.isClusteringInProcess()"></pra-adjuster-loader>'
         )[0];