examples: Remove wrong semicolon in css code

Signed-off-by: Stefan Weil <sw@weilnetz.de>

examples/vector-labels.html

@@ -12,7 +12,7 @@
       h2 {
         font-size: 1.5em;
         line-height: 15px;
-      };
+      }
 
       .scale-cnt {
         margin: 5px;