#6372: Fix select placeholder font-size

netbox/project-static/select.scss

@@ -60,6 +60,7 @@ div.form-floating div.ss-main div.ss-multi-selected {
   div.ss-multi-selected .ss-values .ss-disabled,
   div.ss-single-selected span.placeholder .ss-disabled {
     color: var(--nbx-select-placeholder-color);
+    font-size: $font-size-xs;
   }
 
   .ss-single-selected {