remove Dartnode

Author: egelhaus

README.md

@@ -135,5 +135,3 @@ This repository's source code is available under the [AGPL-3.0 license](LICENSE)
 <p align="center">
   <a href="https://www.g2.com/products/postiz/take_survey" target="blank"><img alt="g2" src="https://github.com/user-attachments/assets/892cb74c-0b49-4589-b2f5-fbdbf7a98f66" /></a>
 </p>
-
-[![Powered by DartNode](https://dartnode.com/branding/DN-Open-Source-sm.png)](https://dartnode.com "Powered by DartNode - Free VPS for Open Source")