rework tag select

src/app/components/shared/_dialogs/create-comment/create-comment.component.html

@@ -5,11 +5,12 @@
         <mat-form-field *ngIf="tags"
                         class="tag-form-field">
           <mat-label>
-            <mat-icon class="icon-svg" svgIcon="comment_tag"></mat-icon>
+            <mat-icon class="icon-svg"
+                      svgIcon="comment_tag"></mat-icon>
             {{'comment-page.tag' | translate}}</mat-label>
           <mat-select [(ngModel)]="selectedTag"
                       class="tag-select">
-            <mat-option value="">{{'comment-page.tag-reset' | translate}}</mat-option>
+            <mat-option>{{'comment-page.tag-reset' | translate}}</mat-option>
             <mat-option *ngFor="let tag of tags"
                         value="{{tag}}">
               {{tag}}