updater: remove TODO related to supporting bundles of apps

Bug: 1128631
Change-Id: I369acff19b10c736ae4cc5f5df6ce06e28d8cc96
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4550106


Reviewed-by: Joshua Pawlicki <waffles@chromium.org>
Commit-Queue: Joshua Pawlicki <waffles@chromium.org>
Auto-Submit: Sorin Jianu <sorin@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1147161}