title: Angular 6 query param in the middle of a routerlink
body: <p>How do you put a parameter into a <code>routerlink</code>.</p>
  
  <p>I'm trying to do something like this:</p>
  
  <pre><code>&lt;p *ngFor="let supplier of suppliers"&gt;
     &lt;a [routerLink]="['/supplier/{{supplier.businessId}}/products']"&gt;
          View Products
     &lt;/a&gt;
  &lt;/p&gt;
  </code></pre>