[lua] Aydeewa Diremite: Remove unused mixin

[UmeboshiXI]

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What does this pull request do?

Removes unused chigoe mixin from Aydeewa Diremite and deletes Aydeewa Diremite mob script since it is no longer needed.

Closes #9539

Through many hours of testing mobskill/shadow mechanics on these mobs on retail, I never saw one spawn a chigoe.

Steps to test these changes

Go to Aydeewa, fight a diremite. See no error in map.exe.