Use Pajamas badge for status on Milestone report

What does this MR do and why?

1. Migrates the status badge on the Milestone report from .status-box to a Pajamas badge component, mirroring the badge used on the Milestones list
2. Changes the label "Past due" in the report badge to "Expired", standardizing terminology with what's used in the Milestone list and in Milestone selectors
3. Adds issuable page specific styling back to this page

This additionally resolves a bug related to the .status-box badge not rendering correctly as a result of moved CSS styles

Screenshots or screen recordings

Before (without bug)	Before	After

How to set up and validate locally

1. Open Milestones with different status, e.g. from http://gdk.test:3000/flightjs/Flight/-/milestones

• To test Expired milestones, create an open Milestone with a due date in the past
• To test Upcoming milestones, create a Milestone with a start date in the future

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.