refactor: change markdown editor code block style

Author: moonrailgun

client/web/src/components/Markdown/editor.less

@@ -66,7 +66,7 @@
         background: rgba(255, 255, 255, 0.1);
       }
       span.cm-comment {
-        color: #6272a4;
+        color: #00dcdb;
       }
       span.cm-string,
       span.cm-string-2 {