refactor(Core/Player): reverse equip item aura duration core fix with a spell correction

[sogladev]

Changes Proposed:

This PR proposes changes to:

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

Allows non-infinite (0 or 21) duration indices to affect auras equipped by items.

Reverts below

• fix(CORE/Player): Apply equip effect auras with -1 duration #14809 (comment)

After analysis of SpellDBC, acore_world.spell_dbc, and acore_world.disables, there is only 1 problematic spell that this PR affects. Every other one has either 0 or 21 set, so reverting this and using a correction is a more proper fix. With a bonus of allowing non-infinite durations on item equip auras to be added by modules.

• reference: find equip item spells with limited duration

The only non-deprecated item this affects is the Shirt of Uber, which is a PTR item to test Ulduar hardmodes. The aura has the same duration as the item's lifetime, so nothing changes for this.

• Shirt of Uber bluepost

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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[avarishd]

Oh, this again... I wonder if my comment was accurate in #14809