Improve docstring for Statevector.evolve (Qiskit#9666)

* Improve docstring for `Statevector.evolve`

I didn't realize from the generated documentation that
`Statevector.evolve` can accept an `Instruction` or `QuantumCircuit`,
not just an `Operator`.  I only learned it once I found myself
reading the source.  This modifies the docstring to make it explicit.

* Disambiguate `Instruction`

Qiskit#9666 (comment)

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Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

qiskit/quantum_info/states/statevector.py

@@ -360,7 +360,7 @@ def evolve(self, other, qargs=None):
         """Evolve a quantum state by the operator.
 
         Args:
-            other (Operator): The operator to evolve by.
+            other (Operator | QuantumCircuit | circuit.Instruction): The operator to evolve by.
             qargs (list): a list of Statevector subsystem positions to apply
                            the operator on.