Delete fetchByIid properties in work items

What does this MR do and why?

This MR cleans up some work item components, after !118060 (merged) hardcoded the fetchByIid to true as part of deprecating the work items global ID route.

Follow-up MRs will clean up the rest of the fetchByIid code

Issue: #393836 (closed)

Screenshots or screen recordings

How to set up and validate locally

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #393836 (closed)