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

Fixes: #1216

src/app/system/manage-surveys/create-survey/create-survey.component.ts

@@ -2,7 +2,7 @@
 import { Component, OnInit } from '@angular/core';
 import { FormGroup, FormBuilder, FormArray, Validators } from '@angular/forms';
 import { Router, ActivatedRoute } from '@angular/router';
-import { MatDialog } from '@angular/material';
+import { MatDialog } from '@angular/material/dialog';
 import { CdkDragDrop, moveItemInArray } from '@angular/cdk/drag-drop';
 
 /** Custom Services */

src/app/system/manage-surveys/manage-surveys.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';
 
 /**
@@ -21,9 +23,9 @@ export class ManageSurveysComponent implements OnInit {
   dataSource: MatTableDataSource<any>;
 
   /** Paginator for manage surveys table. */
-  @ViewChild(MatPaginator) paginator: MatPaginator;
+  @ViewChild(MatPaginator, { static: true }) paginator: MatPaginator;
   /** Sorter for manage surveys table. */
-  @ViewChild(MatSort) sort: MatSort;
+  @ViewChild(MatSort, { static: true }) sort: MatSort;
 
   /**
    * Retrieves the surveys data from `resolve`.