Add ripple everywhere.

frontend/src/app/components/side-menu/side-menu.component.html

@@ -4,7 +4,11 @@
             <img src="assets/images/codiki.png" alt="logo"/>
             Codiki
         </a>
-        <button type="button" (click)="close()" matTooltip="Close the menu" i18n-matTooltip>
+        <button type="button"
+                (click)="close()"
+                matTooltip="Close the menu"
+                matRipple
+                i18n-matTooltip>
             <mat-icon>close</mat-icon>
         </button>
     </h1>