[M138][infra] Roll @chromium-luci package

This updates the pin to the current HEAD of the @chromium-luci package.
This will provide configuration options for generating pyl entries for
mixins and variants and for generating the path to the targets spec
directory relative to the source directory.

The tast_expr argument to skylab was removed, so all instances of that
were removed. The recipe already doesn't read the tast_expr field, so
this shouldn't produce any actual behavior changes.

gn_isolate_map.pyl saw some modifications due to some of the changes
from chromium-luci being rolled in, but that has no impact since
generate_buildbot_json.py hasn't been updated to read the module_scheme
field.

Merge-Approval-Bypass=infra change

(cherry picked from commit 7e937f736c56b5aa195da92bfd853d455bc85e3d)

Change-Id: I9a89bf5f575e3142ad3287db93f5e7d9ac918075
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7218610
Auto-Submit: Garrett Beaty <gbeaty@google.com>
Reviewed-by: Haiyang Pan <hypan@google.com>
Commit-Queue: Haiyang Pan <hypan@google.com>
Cr-Original-Commit-Position: refs/heads/main@{#1553099}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7237042
Commit-Queue: Garrett Beaty <gbeaty@google.com>
Cr-Commit-Position: refs/branch-heads/7204@{#3460}
Cr-Branched-From: d5de512dc9dc8ddfe4e6d71b0637578bb6158683-refs/heads/main@{#1465706}