[Passwords] Unexpire PasswordImport flag

This change unexpires the PasswordImport flag.

Bug: None
Change-Id: Ie93933f7e12b02f5fc7f9850ae48b433595c3cea
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2542790
Commit-Queue: Jan Wilken Dörrie <jdoerrie@chromium.org>
Commit-Queue: Vasilii Sukhanov <vasilii@chromium.org>
Auto-Submit: Jan Wilken Dörrie <jdoerrie@chromium.org>
Reviewed-by: Vasilii Sukhanov <vasilii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#828191}

chrome/browser/flag-metadata.json

@@ -3711,8 +3711,8 @@
   },
   {
     "name": "PasswordImport",
-    "owners": [ "vasilii" ],
-    "expiry_milestone": 88
+    "owners": [ "jdoerrie", "vasilii" ],
+    "expiry_milestone": 92
   },
   {
     "name": "passwords-account-storage",