Change name of section from Sales to Course Seat Purchases

lms/templates/instructor/instructor_dashboard_2/e-commerce.html

@@ -67,7 +67,7 @@ import pytz
       <!-- end wrap -->
       %if section_data['access']['finance_admin']:
       <div class="wrap">
-         <h2>${_("Sales")}</h2>
+         <h2>${_("Course Seat Purchases")}</h2>
          <div>
             %if section_data['total_amount'] is not None:
               <span><strong>${_("Total Credit Card Purchases: ")}</strong></span><span>${section_data['currency_symbol']}${section_data['total_amount']}</span>