Add newline at EOF, again!!

Some VSC default formatter keeps removing it. Stop it already...

Author: Techassi

src/css/admonition.css

@@ -18,4 +18,4 @@
 /* Change color of the "important" admonition back to the default red */
 .doc .admonitionblock.code-rule.warning .icon {
   background-color: #e40046;
-}
+}