fix(metrics): correct dashboard week boundary to Saturday

The dashboard window ended on Sunday instead of Saturday, so mid-week it
requested a different window than the email and missed the warmed cache key.
Align the exclusive end to the most recent Saturday so the page matches the
email window and hits the warm cache.

Part of #1961

Signed-off-by: Alan Peixinho <alan.peixinho@profusion.mobi>

Author: alanpeixinho

dashboard/src/pages/Metrics/MetricsPage.tsx

@@ -551,11 +551,8 @@ function LabsSection({ labs }: { labs: LabData[] }): JSX.Element {
 const getMetricsQueryParams = (
   activeDays: number,
 ): { startDaysAgo: number; endDaysAgo: number } => {
-  const today = new Date();
-  const weekEndDaysAgo = (today.getUTCDay() + 1) % DAYS_IN_WEEK;
-  const endDaysAgo = Math.max(weekEndDaysAgo - 1, 0);
-  const startDaysAgo = endDaysAgo + activeDays;
-  return { startDaysAgo, endDaysAgo };
+  const endDaysAgo = (new Date().getUTCDay() + 1) % DAYS_IN_WEEK;
+  return { startDaysAgo: endDaysAgo + activeDays, endDaysAgo };
 };
 
 export const MetricsPage = (): JSX.Element => {