Extend expiration for Tabs.ScrubDuration histogram

Extend the expiry date of the Tabs.ScrubDuration histogram to a year
later.

Fixed: 1165198
Change-Id: I3073b92cf3b778c57c5a2ad8901a2537405e9a91
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2625155Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Commit-Queue: Richard Chui <richui@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843217}

tools/metrics/histograms/histograms_xml/tab/histograms.xml

@@ -1676,7 +1676,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
-<histogram name="Tabs.ScrubDuration" units="ms" expires_after="M90">
+<histogram name="Tabs.ScrubDuration" units="ms" expires_after="2022-01-12">
   <owner>afakhry@chromium.org</owner>
   <owner>tclaiborne@chromium.org</owner>
   <summary>