Update credits_en.html

we do not use the maps of BEV any more

src/views/credits_en.html

@@ -33,10 +33,6 @@ <h2>Implementation</h2>
 <h2>Sources</h2>
 <p>The texts used for the topics and descriptions is licensed as „Creative Commons Attribution-ShareAlike 3.0 Unported“.
   The pictures shown are drawn from Wikimedia Commons under a free license as indicated on the each individual page on Commons.
-  <br>
-  The maps showing the municipality boundaries were provided by the Bundesamt für Eich- und Vermessungswesen via <a href="https://www.data.gv.at/katalog/dataset/51bdc6dc-25ae-41de-b8f3-938f9056af62" target="_blank" rel="noopener noreferrer">data.gv.at</a>
-  under der license <a href="https://creativecommons.org/licenses/by-sa/2.0/" target="_blank" rel="noopener noreferrer">CC-BY-SA 2.0 AT</a>.
-  Some of the maps used are derivatives of the project maps from <a href="https://github.com/ginseng666/GeoJSON-TopoJSON-Austria" target="_blank">GeoJSON-TopoJSON-Austria</a>.
 </p>
 
 <h2>Licensing</h2>