Add PrankWeb4 citation (#170)

* Add new citation

Author: luk27official

frontend/client/about/about.html

@@ -73,6 +73,12 @@ <h2 id="precomputed-predictions">Precomputed predictions</h2>
     <h2 id="citing"> Citing </h2>
     <p> If you use P2Rank online service, please cite:
     <ul>
+      <li>Lukáš Polák, Petr Škoda, Kamila Riedlová, Radoslav Krivák, Marian Novotný 
+        and David Hoksza.
+        <a href="https://doi.org/10.1093/nar/gkaf421">PrankWeb 4: a modular web server 
+          for protein–ligand binding site prediction and downstream analysis</a>.
+        Nucleic Acids Research. May 2025
+      </li>
       <li>Dávid Jakubec, Petr Škoda, Radoslav Krivák, Marian Novotný
         and David Hoksza.
         <a href="https://doi.org/10.1093/nar/gkac389">PrankWeb 3: accelerated