Bump icalendar from 2.9.0 to 2.10.0

Bumps [icalendar](https://github.com/icalendar/icalendar) from 2.9.0 to 2.10.0.
- [Changelog](https://github.com/icalendar/icalendar/blob/main/History.txt)
- [Commits](icalendar/icalendar@v2.9.0...v2.10.0)

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

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -262,7 +262,7 @@ GEM
       multi_xml (>= 0.5.2)
     i18n (1.14.1)
       concurrent-ruby (~> 1.0)
-    icalendar (2.9.0)
+    icalendar (2.10.0)
       ice_cube (~> 0.16)
     ice_cube (0.16.4)
     ice_nine (0.11.2)