[EP-2447] Preserve cart order after edit

[canac]

Preserve the order of items in the cart after changing one. I'm not sure why the previous code was removing the edited item from the UI, so I removed it. The changed item with the old amount will remain in the list briefly, but the loading indicators will be active until the list refreshes, so I believe that is OK.

Tested in staging ✅

https://jira.cru.org/browse/EP-2447

[wrandall22]

Code looks good, but I'd like to postpone until after peak giving.

[dr-bizz]

Your code looks great! 💯 🔥
One place I can see we can improve is by adding skeletons to the Images in the cart, when the cart items refresh. Currently, after an item is edited or removed the images get reloaded, causing the item's titles to have layout shift to the left.
If we added a skeleton it would show the user the items are refreshing and it would stop the layout shift.
This might be a separate PR, but it could be grouped with this one.

[canac]

@dr-bizz I explicitly set the image dimensions to avoid layout shift. For the record, I only see the layout shift with DevTools open and "Disable cache" checked. Thanks to caching of the images, I don't think that users are experiencing that layout shift.

[dr-bizz]

@dr-bizz I explicitly set the image dimensions to avoid layout shift. For the record, I only see the layout shift with DevTools open and "Disable cache" checked. Thanks to caching of the images, I don't think that users are experiencing that layout shift.

Closing the dev tools seems to ensure it no longer has layout shifts. Thanks

Code freeze is over