remove SkDescriptor API fuzzer

SkDescriptor's programatic API is neither
exposed for untrusted use nor harded for it.
Why are we fuzzing it?

Do we need a change in oss-fuzz before deleting this?

Bug: oss-fuzz:19648
Bug: oss-fuzz:24417
Change-Id: Id8d075938d831ec8cad4014c8fe6efaef46edb55
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/307177
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Reviewed-by: Herb Derby <herb@google.com>
Auto-Submit: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
4 files changed