[Web] Remove SOGo admin login hint (#4100)

* Remove old SOGo Admin Login hint

* Remove unneeded code blocks after change

data/web/lang/lang.ko.json

@@ -696,7 +696,6 @@
         "sieve_preset_7": "Redirect and keep/drop",
         "sieve_preset_8": "Discard message sent to an alias address the sender is part of",
         "sieve_preset_header": "Please see the example presets below. For more details see <a href=\"https://en.wikipedia.org/wiki/Sieve_(mail_filtering_language)\" target=\"_blank\">Wikipedia</a>.",
-        "sogo_allow_admin_hint": "Administrative SOGo logins are only available for mailboxes with an existing SOGo profile. A user must have been logged in to SOGo at least once.",
         "sogo_visible": "Alias is visible in SOGo",
         "sogo_visible_n": "Hide alias in SOGo",
         "sogo_visible_y": "Show alias in SOGo",