There's a user-facing change here. When you tried to update the quantity
of a line item beyond available stock, two things used to happen:
1. A warning was displayed.
2. The item's quantity was updated to the highest possible.
Unfortunately, the logic to update the line item was also reloading the
page and the warning message disappeared before it could be
acknowledged. The easiest fix was to skip the update request. And in my
opinion, it's even better to let the user decide if they still want to
update or cancel the update.
Eventually, we want to replace all this custom Javascript logic with
StimulusJS anyway. So let's not put too much effort into this. It was
important though to resolve the flaky spec which made many builds fail.