When fast deleting properties generalize all outgoing transitions
to mutable instead of generalizing when property is reconfigured.

Bug: chromium:1201938
Change-Id: I080f2f43de1691a742be2a2bec5cd20d02d78dbc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2859960
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74334}