gerrit: Add license header
gerrit: Add license header

BUG=None

Change-Id: I724f3299ac91f5e385e80800b167eab11a67113d
Reviewed-on: https://chromium-review.googlesource.com/c/1354089
Commit-Queue: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@chromium.org>
Reviewed-by: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@chromium.org>

luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go