Update citation guide link on education services page

services/training.md

@@ -49,7 +49,7 @@ Click to [**see all our workshops**][internal/events] and find out more.
 
 [choose-a-license]: <https://choosealicense.com/>
 [open-source-guide/legal]: <https://opensource.guide/legal/>
-[research-software/citation]: <https://research-software.org/citation>
+[research-software/citation]: <https://www.software.ac.uk/how-cite-software>
 [write-the-docs/beginners-guide]: <https://www.writethedocs.org/guide/writing/beginners-guide-to-docs/>
 [internal/events]: {% link events.md %}