Improve Upsert support for check-ins

[adinauer]

Problem Statement

Upserts are currently only available when manually using Sentry.captureCheckIn()

Solution Brainstorm

• A new param for CheckInUtils.withCheckIn()
• Check if there's a @Scheduled annotation on a task annotated with @SentryCheckIn and read schedule from there
• Read schedule from Trigger in quartz
  • CRON expressions in quartz have a different syntax we'd need to support