Add check to preprocess file link hook to not run on webforms

This is a bugfix for the hook introduced in !159 (merged). This hook runs when files are uploaded to webforms which was something I didn't consider. My guess is that since files uploaded in webforms are stored privately, the hook isn't able to grab the string like it would with a publicly stored file. This creates an issue with appending (opens in a new window) to the filename. Since this feature isn't necessary in webforms, I've added a check to skip the hook if the user is currently on a webform.

web/themes/asc_bootstrap_bux/asc_bootstrap_bux.theme

@@ -1147,11 +1147,14 @@ function asc_bootstrap_bux_preprocess_views_exposed_form(&$variables)
  */
 function asc_bootstrap_bux_preprocess_file_link(array &$variables)
 {
-  $link = $variables['link'];
-  $attributes = $link->getUrl()->getOption('attributes');
-  if (isset($attributes['target']) && $attributes['target'] === '_blank') {
-    $string = $link->getText();
-    $string .= " (opens in a new window)";
-    $link->setText($string);
+  $route_name = \Drupal::routeMatch()->getRouteName();
+  if ($route_name !== "entity.webform.canonical") {
+    $link = $variables['link'];
+    $attributes = $link->getUrl()->getOption('attributes');
+    if (isset($attributes['target']) && $attributes['target'] === '_blank') {
+      $string = $link->getText();
+      $string .= " (opens in a new window)";
+      $link->setText($string);
+    }
   }
 }