Issues Analytics: Add iteration to the table

Proposal

One the project level, we want to add the iteration field to the table.

Additional details

Can be found in the epic &7466

Affected files

Issue analytics table: https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/app/assets/javascripts/issues_analytics/components/issues_analytics_table.vue

Implementation Guide

• frontend Add a new column for iteration to the issue analytics table
• frontend Use the iteration.title field from the JSON response for each stage item
• backend Might need to fix the title field for the iteration if its not correctly populated