Revert "[PA/BRP] Enable BRP-ASan on iOS"

This reverts commit d0ba7a18bf38925cf08251f00d156c380062c25e.

Reason for revert: This breaks ios-asan bot. See crbug.com/448077916

Original change's description:
> [PA/BRP] Enable BRP-ASan on iOS
>
> This CL enables BRP-ASan on iOS because now we enabled BRP on iOS.
>
> Bug: 40250685
> Change-Id: I2d235624093d99c38862069bbb0442ec0c30a56f
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6978026
> Reviewed-by: Takashi Sakamoto <tasak@google.com>
> Commit-Queue: Mikihito Matsuura <mikt@google.com>
> Cr-Commit-Position: refs/heads/main@{#1519792}

Bug: 40250685
Change-Id: I59aaeb1372a9f04c260c3a5e735787b55d01c5f6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6997088
Owners-Override: Louis Romero <lpromero@google.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Louis Romero <lpromero@google.com>
Auto-Submit: Louis Romero <lpromero@google.com>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#1522469}