Improvments renderers

client/src/app/instance/search/shared-renderer/components/json-renderer.component.html

-<a *ngIf="value" class="btn btn-outline-primary btn-sm" (click)="openModal(modal)">
+<a *ngIf="isEmpty()" class="btn btn-outline-primary btn-sm" (click)="openModal(modal)">
     JSON
 </a>
 

client/src/app/instance/search/shared-renderer/components/json-renderer.component.ts

@@ -44,4 +44,12 @@ export class JsonRendererComponent extends AbstractRendererComponent {
             Object.assign({}, { class: 'modal-fit-content' })
         );
     }
+
+    isEmpty() {
+        if (!this.value || Object.keys(this.value).length === 0) {
+            return false;
+        } else {
+            return true;
+        }
+    }
 }

client/src/app/instance/search/shared-renderer/components/link-renderer.component.html

 <a *ngIf="value" [href]="getValue()" target="{{(getConfig().blank) ? '_blank' : '_self'}}"
-    [ngClass]="{'btn btn-outline-primary btn-sm': (getConfig().display=='text-button' || getConfig().display=='icon-button')}">
+    [ngClass]="{'btn btn-outline-primary btn-sm btn-block': (getConfig().display=='text-button' || getConfig().display=='icon-button')}">
     <span *ngIf="getConfig().display !== 'icon-button'">{{ getText() }}</span>
     <span *ngIf="getConfig().display === 'icon-button'" class="{{getConfig().icon}}"></span>
 </a>