Update activities/index.md

Co-authored-by: Jan Ainali <[email protected]>

activities/index.md

@@ -24,7 +24,7 @@ Activities that support the above as well as make staff operations work:
 * [Events](events/index.md)
 * [Explaining codebase stewardship](explaining-codebase-stewardship/index.md)
 * [Financial administration](financial-administration/index.md)
-* [Institutional fundraising and grant applications](/grant-applications/index.md)
+* [Institutional fundraising and grant applications](grant-applications/index.md)
 * [Live streaming and podcasting](live-streaming/index.md)
 * [Maintenance of the Standard for Public Code](standard-maintenance/index.md)
 * [Office management](office-management/index.md)