website: Remove Zheming Jin from the workshop schedule

Zheming Jin no longer wishes to present at the gem5 Users' Workshop
2022. He has therefore been removed from the schedule.

Change-Id: Ie186008c358045ee43b0470ad9fe7f2b8671e44c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5-website/+/60490
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: Bobby Bruce <bbruce@ucdavis.edu>