Add error message for invalid email

src/app/password-reset/password-reset.component.html

@@ -4,6 +4,7 @@
     <input matInput #email placeholder="E-Mail" [formControl]="usernameFormControl" [errorStateMatcher]="matcher"
            name="email"/>
     <mat-error *ngIf="usernameFormControl.hasError('required')">Email address is <strong>required</strong>.</mat-error>
+    <mat-error *ngIf="usernameFormControl.hasError('email') && !usernameFormControl.hasError('required')">Email is not <strong>valid</strong>.</mat-error>
   </mat-form-field>
 
   <button mat-raised-button color="primary" (click)="resetPassword(email.value)">Reset password</button>