Remove duplicate middle of screen alerts + mute some areas against some Z-Hack false positives

[Synful-Syn]

Remove duplicate messages in middle of the screen + remove lowest average from anticheat global command

Changes Proposed:

• Removes the duplicate message that appears at the middle of the screen alerting a countermeasure against a fly hacker even if you had the Anticheat.CM.ALERTSCREEN setting disabled.
• Same with jump hack
• Same with advanced jump hack
• Same with ignore-z hack
• Remove the "lowest average" section from the .anticheat global command. It is a silly thing to be seeking for.

Added the following areas to the excluded Ignore-Z hack detection.

• Gnomeregan, some corridor inside the instance, .go xyz -466.640076 260.263092 -208.009796
• Scarlet Monastery, armory, .go xyz 1744.680786 -364.786957 8.011654
• Shadow Labyrinth, boxes inside the instance, .go xyz -409.122559 -120.865135 15.713029
• Botanica, Laj's platform, .go xyz -204.576462 391.573334 -11.178043

Issues Addressed:

• Closes none, I haven't bothered making a bug report.

Tests Performed:

• To test if the messages still appear in the middle, I've reproducted https://github.com/azerothcore/mod-anticheat/issues/111
• Went to the locations I had added and tried to reproduce the Z-hack false positives.

How to Test the Changes:

1. Uhh... compare with an older commit!
2. Play with the Anticheat.CM.ALERTSCREEN setting!

Known Issues and TODO List:

• [ ]

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