chore(examples): add missing semicolon in CSS file from transitions example (#2379)

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small detail in css file

Author: feute

examples/transitions/index.html

@@ -5,7 +5,7 @@
   transition: opacity .5s ease;
 }
 .fade-enter, .fade-leave-active {
-  opacity: 0
+  opacity: 0;
 }
 .child-view {
   position: absolute;