Roadmap settings - Move epics state to sidebar

What does this MR do and why?

Move epics state select from top bar to sidebar on Epics roadmap.

Behind :roadmap_settings feature flag.

Third iteration of roadmap settings migration.

• First iteration: !78626 (merged)
• Second iteration: !79084 (merged)

Screenshots or screen recordings

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

• Turn on feature flag :roadmap_settings
• Visit a non empty roadmap
• Click on Settings in the top right corner
• A drawer with the Roadmap settings title shows up
• Test Epics radio buttons
• URL gets updated when changing options and epics are updated.

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 #345158 (closed)