Adds the last event column to the VSA stage table

What does this MR do and why?

Implements a few minor updates to the VSA stage table

• Remove the sorting option from the title column
• Add an additional column called Last event to the VSA issues / MRs tables
• Add a sorting attribute for the Last event column, the attribute is called end_event
• Rename the Time column to Duration time - Addresses #357824 (closed)
• All changes apply at both the group and project level

Screenshots or screen recordings

Before - Project VSA	After - Project VSA

Before - Group VSA	After - Group VSA

How to set up and validate locally

Creating a group level value stream

1. Ensure you have an EE license, or stub the cycle_analytics_for_groups license feature to true
2. Create a group
3. Create a project within a group (I recommend creating a project from a template such as the rails template)
4. Create a custom value stream for the new group you created
   Note: The first time you create a value stream in a group, a data aggregation needs to run, in gdk this is usually ~10mins, proceed to make a coffee in the meantime, relax ☕ 😎

Seeding data

1. Seed some test VSA data

   $ VSA_SEED_PROJECT_ID=<project-id> VSA_ISSUE_COUNT=10 SEED_VSA=true FILTER=cycle_analytics rake db:seed_fu

2. Navigate to the project value stream, for the project you created

3. Navigate to the group value stream for the group you created

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 #353554 (closed) #357824 (closed)