Fix: AQC returns a wrong circuit when the unitary has a determinant −1

[EgrettaThula]

Summary

Fixes #9327

Details and comments

Simply specifying dtype param of numpy.power() to be complex

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[alexanderivrii]

@EgrettaThula, thank you very much for the bug fix! It seems that you have a slight issue with formatting, a simple way to fix it is to run the command black qiskit test. Also can you please add releasenotes for this fix?

[ajavadia]

thank you for finding this and fixing it too.

[coveralls]

Pull Request Test Coverage Report for Build 3914642425

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 84.853%

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Totals
Change from base Build 3912955231:	0.0%
Covered Lines:	65751
Relevant Lines:	77488

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💛 - Coveralls