Update field UUID references in field condition rules when possible

[brandonkelly]

Description

Keeps fieldUid references within field layouts’ field condition rules updated when a custom field is replaced, whenever possible.

Caveats:

• It only will work if the replaced custom field has the same condition rule class as the former.
• It will only update condition rules within the field layout being saved. Other conditions (custom source conditions, element selection conditions on relational fields, etc.) can’t be updated automatically, unfortunately.

Related issues

• Fixes [5.x]: Replacing a field in a field layout does not update field conditions using that field #19486