Invert the trend colors for the Analytics Exec dashboard

Issue: #382888 (closed)

What does this MR do and why?

Inverts the green/red color of the trend indicator for Lead time for changes, Time to restore service and Change failure rate. In respect to these rows, the lower the value the better. By inverting the color, the user has a better indication of this.

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Enable the Exec dashboard

   Feature.enable(:group_analytics_dashboards_page)

2. Visit the exec dashboard: http://gdk.test:3000/groups/${YOUR_GROUP}/-/analytics/dashboards

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.