Fix continuous signup link to form

Author: Rui Benfeitas

index.md

@@ -63,4 +63,4 @@ Please contact [Rui Benfeitas][8] for questions about the course, or through [ou
 [6]: https://forms.gle/beDNyRoGib9jmFfz8
 [7]: https://join.slack.com/t/omicsintegration/shared_invite/enQtNzQ1MDIzOTkxNTg2LThhMzlkZWY4MDgyM2NjOGVkNmU3YTgxMWE2MWIyNTMwODNmZjJlM2RlY2FhNDViMTU2YjQzMmE5YmUxOTY5ZmU
 [8]: https://nbis.se/about/staff/rui-benfeitas
-[9]: https://forms.gle/YMwtm3XRQVCj8Z5c8
+[9]: https://forms.gle/QfLMskUo8X3uYY3MA