Prevents unauthorized update to schedule

[hariombalhara]

What does this PR do?

As reported on slack, prevents unauthorized update to schedule

Type of change

• Bug fix (non-breaking change which fixes an issue)

How should this be tested?

• Update the schedule and see that it's being updated as earlier
• Update schedule, intercept request and edit schedule ID to some other user's schedule. Check that the request is rejected. Earlier it was accepted and other users' schedule was successfully updated.

Checklist

• I haven't added tests that prove my fix is effective or that my feature works
• I haven't checked if new and existing unit tests pass locally with my changes

[vercel]

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docs – ./apps/docs

🔍 Inspect: https://vercel.com/cal/docs/A2Q9XXS4TEjCkCF5pTSxRYz2YQ6C
✅ Preview: Canceled

calendso – ./apps/web

🔍 Inspect: https://vercel.com/cal/calendso/FgWKh5rDLT3KbcTGjjpG8QFX7jzX
✅ Preview: https://calendso-git-fix-unauthorized-schedule-update-cal.vercel.app