Add Active within last 7 days count to course summary table on the course dashboard

[crathbun428]

User Story
As a course delivery team member, I want to add a count of active learners to the course summary table on the Course Dashboard, so that I am able to quickly see how many learners are currently engaging in my course at the top of the page right when I open the dashboard.

Acceptance Criteria
Given I have access to the Course dashboard
When I view the course summary tableon the Course dashboard
Then I see that a new column has been added between the Course Run and Average Course Grade columns that shows the count of learners active within the past seven days labeled: Active within last 7 days

[crathbun428]

This issue is complete.