Update Nextcloud.php (#2662)

It seems the try in the getInternalUsername function
was not placed very well, so the throw exception in the
ocs_request function didn't work.

sysutils/nextcloud-backup/src/opnsense/mvc/app/library/OPNsense/Backup/Nextcloud.php

@@ -280,15 +280,14 @@ class Nextcloud extends Base implements IBackupProvider
 
     public function getInternalUsername($url, $username, $password): string
     {
-        $xml_response = $this->ocs_request(
-            "$url/ocs/v1.php/cloud/user",
-            $username,
-            $password,
-            "GET",
-            "Cannot get real username"
-        );
-
         try {
+            $xml_response = $this->ocs_request(
+                "$url/ocs/v1.php/cloud/user",
+                $username,
+                $password,
+                "GET",
+                "Cannot get real username"
+            );        
             $data = $xml_response->data;
             if ($data == null) {
                 return $username; // no data found, return the old username