[editor] Replace long dash with n-dash

This dash is a bit shorter.

projects/editor/src/app/text-editor/rich-text-editor.component.html

@@ -195,9 +195,10 @@
     <mat-menu #specialCharsMenu="matMenu" yPosition="above">
       <button mat-button (click)="insertSpecialChar('&nbsp;')"
               [matTooltip]="'Geschütztes Leerzeichen'">&blank;</button>
-      <button mat-button (click)="insertSpecialChar('&#8212;')">&#8212;</button>
+      <button mat-button (click)="insertSpecialChar('&ndash;')">&ndash;</button>
       <button mat-button (click)="insertSpecialChar('&female;')">&female;</button>
       <button mat-button (click)="insertSpecialChar('&male;')">&male;</button>
+      <br>
       <button mat-button (click)="insertSpecialChar('&rsquo;')">&rsquo;</button>
       <button mat-button (click)="insertSpecialChar('&bdquo;')">&bdquo;</button>
       <button mat-button (click)="insertSpecialChar('&ldquo;')">&ldquo;</button>