Fixed reference to episode 9 (was 8)

episodes/10-collaboration-with-others.md

@@ -6,7 +6,7 @@ SPDX-License-Identifier: CC-BY-4.0
 
 # Collaboration with Others
 
-In [episode 8](08-remotes-in-gitlab.md), you already learnt about contributing changes via the local Git repository and the GitLab Web interface.
+In [episode 9](09-remotes-in-gitlab.md), you already learnt about contributing changes via the local Git repository and the GitLab Web interface.
 In this episode, we show you how you can collaborate with other persons on the basis of [Git branches](https://git-scm.com/book/en/v2/Git-Branching-Branches-in-a-Nutshell) and [GitLab Merge Requests](https://docs.gitlab.com/ee/user/project/merge_requests/getting_started.html).
 [branching.pptx](episodes/extras/branching.pptx) provides a summary of the performed steps.