Update expiration of interest-feed-content-suggestions flag

TBR=harringtond@chromium.org

Change-Id: I8204d4f809640d933ae9e0d94e1a9a3921bb01b6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1919742
Commit-Queue: Carlos Knippschild <carlosk@chromium.org>
Auto-Submit: Carlos Knippschild <carlosk@chromium.org>
Reviewed-by: Carlos Knippschild <carlosk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#715923}

chrome/browser/flag-metadata.json

@@ -2438,8 +2438,8 @@
   },
   {
     "name": "interest-feed-content-suggestions",
-    "owners": [ "//chrome/android/feed/OWNERS" ],
-    "expiry_milestone": 80
+    "owners": [ "//chrome/android/feed/OWNERS", "feed@chromium.org" ],
+    "expiry_milestone": 90
   },
   {
     "name": "interest-feed-notifications",