feat: add timezone to datetime display across the board

- the "Flagged Out-of-date on ..." link in the package action panel does
  not contain a timezone specifier.

Signed-off-by: Kevin Morris <kevr@0cost.org>

templates/pkgbase/flag-comment.html

@@ -21,7 +21,7 @@
                 "following reason:"
                 | tr | format("<strong>", username, "</strong>",
                               "<strong>", pkgbase.Name, "</strong>",
-                              "<strong>", flagged_at.strftime("%Y-%m-%d"), "</strong>")
+                              "<strong>", date_display(pkgbase.OutOfDateTS), "</strong>")
                 | safe
             }}
         </p>