Suppress nonsense `DeprecationWarning` caused by `unittest` (backport #12676)

[mergify[bot]]

Summary

unittest.TestCase.assertWarns in context-manager form has an awkward habit of querying the __warningregistry__ attribute on every module in existence. This interacts poorly with a Numpy 2 deprecation warning trigger for code that's attempting to import functions from modules that became private in Numpy 2, if a warning has previously been triggered out of numpy.linalg._linalg.

This simply suppresses that particular warning from the test suite.

Details and comments

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This is an automatic backport of pull request #12676 done by Mergify.

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[coveralls]

Pull Request Test Coverage Report for Build 9714396574

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 6 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.02%) to 89.959%

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Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/expr.rs	1	94.02%
crates/qasm2/src/lex.rs	5	92.11%
<!--	Total:	6		-->

Totals
Change from base Build 9685829487:	0.02%
Covered Lines:	61853
Relevant Lines:	68757

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💛 - Coveralls