Revert "Add launch screen to iOS apps"

This reverts commit bf8dad281e724324d774aa4753a674a5a597b0b8.

Reason for revert: Need to fix infra Housekeeper bot

Original change's description:
> Add launch screen to iOS apps
> 
> Bug: skia:
> Change-Id: I7ebe94213c26c31c1b0dbd1b8951f87263cd41a3
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/175826
> Commit-Queue: Jim Van Verth <jvanverth@google.com>
> Reviewed-by: Hal Canary <halcanary@google.com>

TBR=jvanverth@google.com,halcanary@google.com,benjaminwagner@google.com

Change-Id: Ie540cc4d3209cf5e92d4c66812243721b1ac7fc2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/239105
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
6 files changed