Work Items - Preserve data in system notes on deletion

When we delete widget data, especially when changing work item types, we want to preserve the data as part of the System Notes.

We already do this for some data, e.g. Labels or Assignees, where the system note is "Removed sectiondev groupproduct planning" or "Unassigned @nicolasdular", but for other data we don't do this yet.

Example

Before	After
"Removed Health Status"	"Removed Health Status Needs Attention"

Note: We should check with TW what's the best wording.