Filter aer warnings in deprecated FakeBackend V1 class (backport #13018)

[mergify]

Summary

The recent qiskit-aer 0.15 release has introduced deprecation warnings for BackendV1 inputs in NoiseModel.from_backend. We were using this method in the deprecated FakeBackend class (which is, by definition, V1) and this is triggering test failures. I suggest filtering the warnings in FakeBackend until the class is removed in 2.0.

Details and comments

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This is an automatic backport of pull request #13018 done by [Mergify](https://mergify.com).

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[coveralls]

Pull Request Test Coverage Report for Build 10525115495

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 11 unchanged lines in 5 files lost coverage.
• Overall coverage increased (+0.006%) to 89.816%

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Files with Coverage Reduction	New Missed Lines	%
qiskit/circuit/instruction.py	1	95.64%
qiskit/providers/backend_compat.py	1	89.19%
crates/qasm2/src/expr.rs	1	94.02%
qiskit/transpiler/passes/synthesis/unitary_synthesis.py	2	88.39%
crates/qasm2/src/lex.rs	6	91.73%

Totals
Change from base Build 10506117955:	0.006%
Covered Lines:	66810
Relevant Lines:	74385

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💛 - Coveralls