build: update to angular-v9.1.12 (#1215)

Fixes: #1216

src/app/system/manage-scheduler-jobs/manage-scheduler-jobs.component.ts

@@ -1,6 +1,8 @@
 /** Angular Imports */
 import { Component, OnInit, ViewChild } from '@angular/core';
-import { MatTableDataSource, MatPaginator, MatSort } from '@angular/material';
+import { MatPaginator } from '@angular/material/paginator';
+import { MatSort } from '@angular/material/sort';
+import { MatTableDataSource } from '@angular/material/table';
 import { ActivatedRoute } from '@angular/router';
 import { SelectionModel } from '@angular/cdk/collections';
 
@@ -29,9 +31,9 @@ export class ManageSchedulerJobsComponent implements OnInit {
   selection = new SelectionModel<any>(true, []);
 
   /** Paginator for table. */
-  @ViewChild(MatPaginator) paginator: MatPaginator;
+  @ViewChild(MatPaginator, { static: true }) paginator: MatPaginator;
   /** Sorter for manage scheduler jobs table. */
-  @ViewChild(MatSort) sort: MatSort;
+  @ViewChild(MatSort, { static: true }) sort: MatSort;
 
   /**
    * Retrieves the scheduler jobs data from `resolve`.