Revert "Move libassistant DEPS from src_internal to src"

This reverts commit a530f4f3.

Reason for revert: This breaks canary release crbug/1425561. This change also includes src-internal roll.

Original change's description:
> Move libassistant DEPS from src_internal to src
>
> This change moves libassistant-related dependencies from src_internal to src as a part of chromium browser on git submodule migration.
>
> Bug: 1409738
> Change-Id: I297ed3f88c15379c0962667e3354b7668fb09cd5
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4338029


> Reviewed-by: Tao Wu <wutao@chromium.org>
> Commit-Queue: Aravind Vasudevan <aravindvasudev@google.com>
> Cr-Commit-Position: refs/heads/main@{#1118449}

Bug: 1409738
Change-Id: I6f9897ba739d71cee98fe18fb0cddd010eb9be50
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4351087


Auto-Submit: Aravind Vasudevan <aravindvasudev@google.com>
Reviewed-by: Josip Sokcevic <sokcevic@chromium.org>
Commit-Queue: Josip Sokcevic <sokcevic@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1118879}