Bump @fullcalendar/core from 6.1.17 to 6.1.18

Bumps [@fullcalendar/core](https://github.com/fullcalendar/fullcalendar/tree/HEAD/packages/core) from 6.1.17 to 6.1.18.
- [Release notes](https://github.com/fullcalendar/fullcalendar/releases)
- [Changelog](https://github.com/fullcalendar/fullcalendar/blob/main/CHANGELOG.md)
- [Commits](https://github.com/fullcalendar/fullcalendar/commits/v6.1.18/packages/core

)

---
updated-dependencies:
- dependency-name: "@fullcalendar/core"
  dependency-version: 6.1.18
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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