In live bs-searchboxes, also search on input (i.e. paste).

This should resolve the titular issue in Charcoal-SE#941 of pasting a
domain name in the new domain link dialog not triggering a
search and fill of the available domains.

app/javascript/util.js

@@ -106,7 +106,7 @@ export function installSelectpickers() {
       noneResultsText: 'No results matched your search or you need to enter more characters to search with.'
     });
 
-    $(e).parent().find('.bs-searchbox input[type="search"]').on('keydown', ev => {
+    $(e).parent().find('.bs-searchbox input[type="search"]').on('keydown input', ev => {
       if ($(ev.target).val().length < 2) {
         return;
       }