New copy for the Unreviewed suggestions insights chart (#2375)

pontoon/insights/templates/insights/widgets/insights.html

@@ -51,9 +51,9 @@
         <section class="half">
             <div class="block clearfix">
                 <h3 class="controls">
-                    Unreviewed suggestions lifespan
+                    Age of unreviewed suggestions
                     {{ Tooltip.display(
-                        intro='How much time it takes on average to review a suggestion.',
+                        intro='How old are the unreviewed suggestions on average at a particular point in time.',
                     ) }}
                 </h3>
                 <canvas

specs/0108-community-health-dashboard.md

@@ -39,7 +39,7 @@ A line chart showing the average age of suggestions still unreviewed in a partic
 
 Data is available for each day, but aggregated by month in the chart. A tooltip showing the exact data at a given month appears when hovering over a chart.
 
-**Text for infobox**: How old are on average the suggestions currently unreviewed.
+**Text for infobox**: How old are the unreviewed suggestions on average at a particular point in time.
 
 ## Time to review suggestions