change button link to a link for pagination for indexation with rendertron

src/app/shared/components/paginator/paginator.component.html

@@ -31,11 +31,13 @@
       <ul>
         <ng-container *ngFor="let pageNum of getPages(); let i = index">
           <li>
-            <button *ngIf="!loading; else pageNumberDisabled"
-            [attr.aria-label]="pageNum"
-            (click)="onPage(pageNum)" class="button"
-              [ngClass]="{'is-current': pageNum === pageIndex}"
-              [attr.aria-current]="pageNum === pageIndex ? 'page' : undefined">{{ pageNum }}</button>
+            <a *ngIf="!loading; else pageNumberDisabled"
+                [attr.aria-label]="pageNum"
+                (click)="onPage(pageNum);" class="button"
+                href="{{ currentUrl }}?page={{ pageNum }}"
+                [ngClass]="{'is-current': pageNum === pageIndex}"
+                [attr.aria-current]="pageNum === pageIndex ? 'page' : undefined">{{ pageNum }}</a>
+
             <ng-template #pageNumberDisabled>
               <button class="button" [ngClass]="{'is-current': pageNum === pageIndex}"
                       [attr.aria-current]="pageNum === pageIndex ? 'page' : undefined" disabled>{{ pageNum }}</button>

src/app/shared/components/paginator/paginator.component.ts

 import { Component, OnInit, Input, Output, EventEmitter } from '@angular/core';
 import { ViewportScroller } from '@angular/common';
+import { Router } from '@angular/router';
 
 @Component({
   selector: 'app-paginator',
@@ -20,12 +21,16 @@ export class PaginatorComponent implements OnInit {
   @Output() pageSizeChanged = new EventEmitter<number>();
 
   pageSizeDropdownToggle = false;
+  currentUrl: string;
 
   constructor(
     private _viewportScroller: ViewportScroller,
+    private _router: Router
   ) { }
 
   ngOnInit() {
+    const url = this._router.url.split('?');
+    this.currentUrl = url[0];
   }
 
   onPrev() {
@@ -42,9 +47,11 @@ export class PaginatorComponent implements OnInit {
     }
   }
 
-  onPage(n: number): void {
+  onPage(n: number): boolean {
     this.scrollTop();
     this.page.emit(n);
+
+    return false;
   }
 
   totalPages(): number {