Unnecessary re renders

### Issue type

* [x] bug report
* [ ] feature request

### Issue description

**Current behavior:**
Components are re-rendering for unnecessary reasons. For example when I scroll the page, or hover menu items, ... components are re-rendering HTML.

**Expected behavior:**
Re-render components just when needed.

**Steps to reproduce:**
Use the following code with ngx-admin starter-kit:

**Related code:**
dashboard.component.ts:

```
import {Component} from '@angular/core';

@Component({
selector: 'ngx-dashboard',
templateUrl: './dashboard.component.html',
})
export class DashboardComponent {
constructor() {}

checkUpdate() {
console.log('component is re-rendering!!!');
return 1;
}
}

```

dashboard.component.html
```