Remove undefined variable

[Randl]

Fix #10113

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[coveralls]

Pull Request Test Coverage Report for Build 5021608130

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• 16 unchanged lines in 4 files lost coverage.
• Overall coverage increased (+0.03%) to 85.933%

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Files with Coverage Reduction	New Missed Lines	%
qiskit/transpiler/passes/synthesis/unitary_synthesis.py	1	90.25%
crates/qasm2/src/lex.rs	3	90.63%
qiskit/circuit/parameterexpression.py	5	87.84%
qiskit/circuit/library/data_preparation/pauli_feature_map.py	7	90.59%

Totals
Change from base Build 4982201939:	0.03%
Covered Lines:	71245
Relevant Lines:	82908

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💛 - Coveralls

[jakelishman]

Cool, thanks for finding this and for the quick fix! Would you be able to add a test of the error message and a short bug-fix release note about it?

[jakelishman]

Super, thanks!