fix(Core/Items): Fix exploit where multiple auras could be applied from a single enchantment.

[walkline]

Changes Proposed:

There is a critical exploit at the moment. When you are dead and have previously equipped an item with this enchantment (and possibly some others), if you attempt to replace it with another item while dead (it will throw an error, but this can be ignored), upon resurrection, you will have multiple enchantment auras - equal to the number of times you tried to equip the item. As a result, you can turn your character into a raid boss.

Here is the video that demonstrates that - https://youtu.be/1FtL7aiU7Mc.

Honestly, I'm not very familiar with the spell system and don't know exactly how everything works, but with every attempt to equip a new item, we are adding an aura to m_ownedAuras, which is eventually added to m_appliedAuras upon resurrection.

This PR proposes changes to:

• Core (units, players, creatures, game systems).
• Scripts (bosses, spell scripts, creature scripts).
• Database (SAI, creatures, etc).

Issues Addressed:

• Closes

SOURCE:

The changes have been validated through:

• Live research (checked on live servers, e.g Classic WotLK, Retail, etc.)
• Sniffs (remember to share them with the open source community!)
• Video evidence, knowledge databases or other public sources (e.g forums, Wowhead, etc.)
• The changes promoted by this pull request come partially or entirely from another project (cherry-pick). Cherry-picks must be committed using the proper --author tag in order to be accepted, thus crediting the original authors, unless otherwise unable to be found

Tests Performed:

This PR has been:

• Tested in-game by the author.
• Tested in-game by other community members/someone else other than the author/has been live on production servers.
• This pull request requires further testing and may have edge cases to be tested.

How to Test the Changes:

• This pull request can be tested by following the reproduction steps provided in the linked issue
• This pull request requires further testing. Provide steps to test your changes. If it requires any specific setup e.g multiple players please specify it as well.

Known Issues and TODO List:

• [ ]
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