🐛 fix deprecated Loader.load_module()

[burgholzer]

Summary

This PR ports a fix from Qiskit/rustworkx#728 that fixes the following ImportWarning under Python>=3.10

ImportWarning: QiskitLoader.exec_module() not found; falling back to load_module()

Details and comments

Some further context can be found in the corresponding retworkx PR Qiskit/rustworkx#728.
The underlying code was introduced in #5089.

Fixes #8853.

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[jakelishman]

Thanks - I always forget the exact particulars of the import system, but this looks about right to me. I don't think there are any modules that are supposed to be "executed" (like programs) in Qiskit anyway.

[coveralls]

Pull Request Test Coverage Report for Build 3437210643

• 4 of 4 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.0008%) to 84.568%

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Totals
Change from base Build 3436589478:	0.0008%
Covered Lines:	62427
Relevant Lines:	73819

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💛 - Coveralls

[burgholzer]

Just saw that CI wasn't really happy. Added a corresponding docstring to please the linter.

[jakelishman]

Ah, thanks - sorry, I'd also not noticed that the PR had got stuck. It's a bit of a silly lint rule for things like this, but elsewhere it does help ensure that all our public API gets at least some documentation.