fix(form): dropdown item description gets wrong state class

When a dropdown item has got a description, every added state class like error also styles such extra items by accident

Author: lubber-de

src/definitions/collections/form.less

@@ -623,7 +623,7 @@
     .ui.form .fields.@{state} .field .ui.dropdown,
     .ui.form .fields.@{state} .field .ui.dropdown .item,
     .ui.form .field.@{state} .ui.dropdown,
-    .ui.form .field.@{state} .ui.dropdown .text,
+    .ui.form .field.@{state} .ui.dropdown > .text,
     .ui.form .field.@{state} .ui.dropdown .item {
       background: @bg;
       color: @c;