Angular modules get added with weights 200+ so bump theme to 290

This means custom CSS also needs to be bumped above 290.

Until civicrm/civicrm-core#20278 is merged,
there is no easy way to identify which snippet is the custom CSS one so
we search for 'custom.css' in the name.

finsburypark.php

@@ -37,7 +37,11 @@ function finsburypark_civicrm_alterBundle(CRM_Core_Resources_Bundle $bundle) {
   if ($bundle->name == 'coreStyles') {
     $bundle->filter(function($snippet) {
       if ($snippet['name'] == 'civicrm:css/civicrm.css') {
-        $snippet['weight'] = 90;
+        $snippet['weight'] = 290;
+        return $snippet;
+      }
+      elseif (($snippet['name'] == 'civicrm::css/custom.css') or (strpos($snippet['name'], 'custom.css') !== false)) {
+        $snippet['weight'] = 300;
         return $snippet;
       }
       return TRUE;