Fix AnnotatedOperation being modified during parameter assignment (backport #12869)

[mergify]

Summary

Copying an annotated operation currently does not copy the underlying base_op. This leads to problems down the line, as we have multiple annotated operations referencing the same base_op, for example in parameter assignment. This PR copies the base_op upon copying the annotated operation to fix this problem.

Details and comments

No reno (yet), as this bug was probably mostly noticable in this release (1.2) which adds parameter handling to AnnotatedOperation.

Here's a minimal breaking example, which is fixed by this PR.

from qiskit.circuit import Parameter, QuantumCircuit
from qiskit.circuit.library import RYGate

theta = Parameter("theta")
ry = RYGate(theta)
qc = QuantumCircuit(5)
qc.append(ry.control(4, annotated=True), qc.qubits)
qc.assign_parameters([1.23])
print(qc)  # prints the circuit, which should be unmodified, with a bound parameter

qc.assign_parameters([1.23])  # fails as the parameter is already bound

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This is an automatic backport of pull request #12869 done by [Mergify](https://mergify.com).

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[coveralls]

Pull Request Test Coverage Report for Build 10184376926

Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• 17 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.02%) to 89.829%

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Files with Coverage Reduction	New Missed Lines	%
qiskit/transpiler/passes/synthesis/unitary_synthesis.py	2	88.39%
crates/qasm2/src/lex.rs	3	91.98%
crates/qasm2/src/parse.rs	12	96.23%

Totals
Change from base Build 10183294285:	-0.02%
Covered Lines:	66432
Relevant Lines:	73954

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💛 - Coveralls