Issue #3346599: Fix php error when accessing OpenStackProvideradminSettingsForm

modules/tenants/openstack_provider/src/Form/Config/OpenStackProviderAdminSettingsForm.php

@@ -277,7 +277,7 @@ class OpenStackProviderAdminSettingsForm extends ConfigFormBase {
       ],
     ];
 
-    $vpc_id = $form['aws']['network']['vpc']['#value'];
+    $vpc_id = !empty($form['aws']['network']['vpc']['#value']) ? $form['aws']['network']['vpc']['#value'] : '';
 
     $form['aws']['network']['public_subnet_1'] = [
       '#type' => 'select',