Bump ical4j from 3.0.18 to 3.0.19
Bump ical4j from 3.0.18 to 3.0.19

Bumps [ical4j](https://github.com/ical4j/ical4j) from 3.0.18 to 3.0.19.
- [Release notes](https://github.com/ical4j/ical4j/releases)
- [Changelog](https://github.com/ical4j/ical4j/blob/develop/CHANGELOG.md)
- [Commits](https://github.com/ical4j/ical4j/compare/ical4j-3.0.18...ical4j-3.0.19)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
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