title: Pipe doesn't update the template when remove a item from array
body: <p>I was not able to refresh the template after I have removed the item from <code>pages</code> array due to <code>normalizeUri</code> pipe. Same code is working fine without <code>normalizeUri</code> pipe. Can you tell me what was the issue of pipe implementation? i.e. Why template doesn't update if there is pipe.    </p>
  
  <p><em>.html</em></p>
  
  <pre><code>  &lt;ion-slides pager (ionSlideDidChange)="slideChanged()"&gt;
      &lt;ion-slide *ngFor='let page of pages | normalizeUri'&gt;
        &lt;img [src]='page' /&gt;
      &lt;/ion-slide&gt;
    &lt;/ion-slides&gt;
  </code></pre>
  
  <p><em>.ts</em></p>
  
  <pre><code>  async removePage() {
      try {
  
        await SbSdk.removePage({ page: this.selectedPage });
        let pageIndexToRemove = null;
        this.pages.forEach((p, index) =&gt; {
          if (this.selectedPage.pageId === p.pageId) {
            pageIndexToRemove = index;
          }
        });
  
        this.pages.splice(pageIndexToRemove, 1);
        this.selectedPage = null;
  
        if (this.pages.length == 0) {//no pages
          this.goToScan();
          return;
        } else {
          setTimeout(() =&gt; {
            this.goToSlide(this.pages.length - 1);
          }, 500);
        }
        this.changeDetector.detectChanges();
      }
      catch (err) {
        console.log(err);
      }
    }
  </code></pre>
  
  <p>pipe.ts</p>
  
  <pre><code>import { Pipe, PipeTransform } from '@angular/core';
  import { ImageHandlingProvider } from '../../providers/image-handling/image-handling';
  import { Page } from 'cordova-plugin-scanbot-sdk';
  
  @Pipe({
    name: 'normalizeUri',
  })
  export class NormalizeUriPipe implements PipeTransform {
  
    constructor(private imageHandlingProvider: ImageHandlingProvider) { }
    transform(pages: Page[]): string[] {
      return pages.map((p) =&gt; {
        return this.imageHandlingProvider.normalizeImageFileUri(p.documentPreviewImageFileUri || p.originalPreviewImageFileUri);
      });
    }
  
  }
  </code></pre>