[skp] Validate image lattice counts

Bug: 502103414
Fixed: 502440240
Change-Id: Id13b2dfd30830c238d19914f3231f76383cee80b
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1208956
Reviewed-by: Kaylee Lubick <kjlubick@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Auto-Submit: Michael Ludwig <michaelludwig@google.com>
(cherry picked from commit 3d08a21145b080f644d6b6a621ae33a452d27a35)
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1209736