Update active lucicfg experiments.

Remove retired noop experiments and add the one needed for the
ongoing luci-scheduler.cfg format migration.

Change-Id: Ib49bca8384086d73b2d5722e4f1f6429c54fa2be
Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/3451136
Reviewed-by: Mirko Bonadei <mbonadei@chromium.org>
Commit-Queue: Mirko Bonadei <mbonadei@chromium.org>

• cr-buildbucket.cfg[diff]
• luci-scheduler.cfg[diff]
• main.star[diff]
• project.cfg[diff]
• realms.cfg[diff]