Draft: Add message to modal explaining that sole owners can't be removed

What does this MR do and why?

Related to #24047 (closed)

Adds a tooltip explaining why a sole owner of a group or project can not be removed.

Screenshots or screen recordings

Trying to remove yourself from a group

An admin trying to remove the last owner from a group

Trying to remove yourself from a personal project

An admin trying to remove the last owner from a personal project

How to set up and validate locally

Trying to remove yourself from a group

1. Navigate to a group you are an Owner of
2. Change all the roles so you are the only Owner

An admin trying to remove the last owner from a group

1. Sign in as an Admin
2. Navigate to a group you are not a member of
3. Change roles so there is only one Owner
4. Try to remove that Owner

Trying to remove yourself from a personal project

1. Create a personal project
2. Try to Leave that personal project

An admin trying to remove the last owner from a personal project

1. Sign in as an Admin
2. Navigate to a personal project that is not yours
3. Try to remove the creator of the personal project

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.