Core/Auth: Mitigate DoS attacks to authserver

Mitigate DoS attacks to authserver like "Wow Auth Flooder.exe" by allowing a finite number of AUTH_LOGON_CHALLEGE packets in a row from same socket, 3 sounds like a reasonable limit.
Merge branch 'authserver_fix_dos' of github.com:jackpoz/TrinityCore
DB/SAI: Blighted last rites

By @dr-j fixes #9172
Core/Spells: Fixed summoning players after recent changes
Merge branch 'master' of github.com:TrinityCore/TrinityCore into mmaps_rw