Update expiry of ChromeOS.CWP.CollectProcessTypes.

We are continuing data collection from this histogram.

Bug: 1167829
Change-Id: I2114321350cf2ae940b2239eb82eebd243e436c8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2638073Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Mark Pearson <mpearson@chromium.org>
Commit-Queue: Bin Du <dubin@google.com>
Cr-Commit-Position: refs/heads/master@{#845301}

tools/metrics/histograms/histograms_xml/chromeos/histograms.xml

@@ -271,7 +271,7 @@ incoming reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="ChromeOS.CWP.CollectProcessTypes"
-    enum="ChromeOSProcessTypeCollectionStatus" expires_after="2021-03-01">
+    enum="ChromeOSProcessTypeCollectionStatus" expires_after="2022-01-19">
   <owner>aalexand@google.com</owner>
   <owner>cwp-team@google.com</owner>
   <summary>