Remove the `:consolidated_edit_button` feature flag

What does this MR do and why?

Removes the :consolidated_edit_button feature flag. The feature was delivered as a part of the issue: #221247 (closed)

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 #270433 (closed)