Add icon to issues on child epics when filtering epics

What does this MR do and why?

This MR is basically to determine if an issue belongs to a child epic when filtering by epic, and show an indicator icon with a tooltip that says: "This issue is in a child-epic of the filtered epic".

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

Before	After

How to set up and validate locally

Prerequisites:

1. GitLab Ultimate enabled on local GDK.
2. Create Epics with child epics and few issues under it like mentioned in the docs

Steps to verify:

1. Login with any user
2. Go to any Project > Issues > List
3. Search by parent Epic id
4. Check if an information icon appears besides the name to indicate that the issue is of child epic

Related to #213002 (closed)