[resultui] Use `npm ci` for release builds.
[resultui] Use `npm ci` for release builds.

It appears to be more appropriate based on
https://stackoverflow.com/a/53325242

R=weiweilin@google.com, e609d4c46132d2dea94acf5ac2b9f229ffc1f245@chromium.org

Change-Id: I457e1905087ff581bbf13f11d89b87865d54698f
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/2170607
Reviewed-by: Joey Scarr <e609d4c46132d2dea94acf5ac2b9f229ffc1f245@chromium.org>
Commit-Queue: Vadim Shtayura <9f116ddb1b24f6fc1916a676eb17161b6c07dfc1@chromium.org>

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