Search only active milestones on issues list refactor

What does this MR do and why?

This MR shows only active milestones in the filtered search bar of the issues list refactor, as a follow up of !79945 (comment 832728320). This is to mimic the Haml issues list behaviour.

This MR also:

• Removes code in epic_token.vue that duplicates code in base_token.vue (logic already exists in base_token.vue#L98-105)
• Makes issuable_list_root.vue not use html5 drag and drop so we can test it with capybara (when vue_issues_list FF is enabled, the feature spec in issues_spec.rb#L165-181 will pass)

Behind feature flag vue_issues_list defaulted to off

Screenshots or screen recordings

Current HAML milestones	Current Vue refactor milestones (incorrectly shows v0.0, v2.0, v3.0, v4.0)	Fixed Vue refactor milestones

How to set up and validate locally

1. In rails console enable the feature flag

   Feature.enable(:vue_issues_list)

2. Visit any group or project issues page such as http://127.0.0.1:3000/h5bp/html5-boilerplate/-/issues/
3. Test the MR

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.