Merge branch 'Fix-HZDR-workshop-dates-2021' into 'master'

_events/2021/07/2021-07-16-python.md

_events/2021/08/2021-08-13-git-and-gitlab.md

_events/2021/08/2021-08-13-python.md

_events/2021/09/2021-09-17-python.md

_events/2021/10/2021-10-15-git-and-gitlab.md

_events/2021/11/2021-11-12-python.md

_events/2021/12/2021-12-10-git-and-gitlab.md