Bump icalendar from 5.0.13 to 6.0.1 (#2500)

Bumps [icalendar](https://github.com/collective/icalendar) from 5.0.13 to 6.0.1.
- [Release notes](https://github.com/collective/icalendar/releases)
- [Changelog](https://github.com/collective/icalendar/blob/main/CHANGES.rst)
- [Commits](collective/icalendar@v5.0.13...v6.0.1)

---
updated-dependencies:
- dependency-name: icalendar
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -3,7 +3,7 @@ argparse==1.4.0
 filelock==3.16.1
 gspread==6.1.3
 humanize>=0.5.1
-icalendar==5.0.13
+icalendar==6.0.1
 Jinja2==3.1.4
 libmozdata==0.2.8
 numpy==2.1.1