Put paneSearch back and hide it

If #paneSearch is missing dokka's ReactJS crashes and doesn't generate the search button.

Author: TheElectronWill

scala3doc/resources/dotty_res/styles/scalastyle.css

@@ -126,6 +126,9 @@ th {
   height: 100%;
   font-size: var(--leftbar-font-size);
 }
+#paneSearch {
+  display: none;
+}
 #logo {
   background-size: contain;
   background-repeat: no-repeat;

scala3doc/src/dotty/renderers/ScalaHtmlRenderer.scala

@@ -233,6 +233,7 @@ class ScalaHtmlRenderer(ctx: DokkaContext) extends SiteRenderer(ctx) {
                     div(id := "container")(
                         div(id := "leftColumn")(
                             div(id := "logo"),
+                            div(id := "paneSearch"),
                             nav(id := "sideMenu"),
                         ),
                         div(id := "main")(