UI: disabled filtering of attributes with empty string values for attribute talbe

ui-ngx/src/app/modules/home/components/attribute/attribute-table.component.html

@@ -186,6 +186,7 @@
               <div fxFlex fxLayout="row" style="overflow: hidden; align-items: center;">
                 <span class="ellipsis">{{attribute.value | tbJson}}</span>
                 <tb-copy-button
+                  *ngIf="attribute.value !== ''"
                   class="attribute-copy"
                   [disabled]="isLoading$ | async"
                   [copyText]="attribute.value | tbJson"

ui-ngx/src/app/modules/home/models/datasource/attribute-datasource.ts

@@ -89,7 +89,7 @@ export class AttributeDatasource implements DataSource<AttributeData> {
                   pageLink: PageLink): Observable<PageData<AttributeData>> {
     return this.getAllAttributes(entityId, attributesScope).pipe(
       map((data) => {
-        const filteredData = data.filter(attrData => attrData.lastUpdateTs !== 0 && attrData.value !== '');
+        const filteredData = data.filter(attrData => attrData.lastUpdateTs !== 0);
         return pageLink.filterData(filteredData);
       })
     );