Bump icalendar from 2.12.2 to 2.12.3 (#4635)

Bumps [icalendar](https://github.com/icalendar/icalendar) from 2.12.2 to 2.12.3.
- [Changelog](https://github.com/icalendar/icalendar/blob/main/CHANGELOG.md)
- [Commits](https://github.com/icalendar/icalendar/compare/v2.12.2...v2.12.3)

---
updated-dependencies:
- dependency-name: icalendar
  dependency-version: 2.12.3
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Gemfile.lock

@@ -355,7 +355,7 @@ GEM
       terminal-table (>= 1.5.1)
     i18n_data (1.1.0)
       simple_po_parser (~> 1.1)
-    icalendar (2.12.2)
+    icalendar (2.12.3)
       base64
       ice_cube (~> 0.16)
       logger