mgr/dashboard: show loader while changing pages

during server side pagination where each pagination cycle is delayed by
1s.

Fixes: https://tracker.ceph.com/issues/72979
Signed-off-by: Nizamudeen A <[email protected]>

Author: nizamial09

src/pybind/mgr/dashboard/frontend/src/app/shared/datatable/table/table.component.ts

@@ -905,6 +905,7 @@ export class TableComponent implements AfterViewInit, OnInit, OnChanges, OnDestr
     this.userConfig.limit = this.model.pageLength;
 
     if (this.serverSide) {
+      this.loadingIndicator = true;
       this.reloadData();
       return;
     }