13911 | Add ignoring of RuntimeWarning of aer in GenericBackendV2 test (backport #13912)

[mergify]

Summary

Because the aer isn't available on all envs, the test logs get flooded with sometimes meaningless DeprecationWarnings.

This PR adds that the affected class's error gets ignored in the tests.

Fixes #13911

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This is an automatic backport of pull request #13912 done by Mergify.

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[coveralls]

Pull Request Test Coverage Report for Build 13718963243

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 25 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.01%) to 88.842%

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Files with Coverage Reduction	New Missed Lines	%
crates/accelerate/src/unitary_synthesis.rs	1	93.21%
crates/qasm2/src/lex.rs	6	91.48%
crates/qasm2/src/parse.rs	18	96.69%

Totals
Change from base Build 13716591116:	-0.01%
Covered Lines:	79382
Relevant Lines:	89352

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💛 - Coveralls