RA.MinLevel to Ra.MinLevel (#18387)

Solves https://github.com/TrinityCore/TrinityCore/issues/18386

src/server/worldserver/RemoteAccess/RASession.cpp

@@ -135,7 +135,7 @@ bool RASession::CheckAccessLevel(const std::string& user)
 
     Field* fields = result->Fetch();
 
-    if (fields[1].GetUInt8() < sConfigMgr->GetIntDefault("RA.MinLevel", 3))
+    if (fields[1].GetUInt8() < sConfigMgr->GetIntDefault("Ra.MinLevel", 3))
     {
         TC_LOG_INFO("commands.ra", "User %s has no privilege to login", user.c_str());
         return false;