### What?
This fix prevents custom row labels being removed when duplicating array
items.
### Why?
Currently, when you have an array with custom row labels, if you create
a new array item by duplicating an existing item, the new item will have
no custom row label until you refresh the page.
### How?
During the `duplicate` process, we remove any react components from the
field state. This change intentionally re-adds the `RowLabel` if one
exists.
#### Reported by client
37c945b95b