fix link

index.md

@@ -47,7 +47,7 @@ and install a Python interpreter.
 - The template of these pages is adapted from [The Carpentries Lesson Template][styles].
 - Sections of this course material use data obtained from the [EU Open Data Portal][eu-odp], licensed under [CC-BY 4.0][cc-by-legal].
   A copy of this data is included in the [source repository](https://git.embl.de/grp-bio-it-workshops/intermediate-python).
-- The lockdown data used in [Working with Data](../02-data/) was adapted from
+- The lockdown data used in [Working with Data](02-data/) was adapted from
 [this Wikipedia page](https://en.wikipedia.org/wiki/COVID-19_pandemic_lockdowns#table-of-pandemic-lockdowns),
 accessed on 2020-06-24.