Rotate qubit operator by exponential of Pauli.

Perform the rotation e^{-i \theta * P}Qe^{i \theta * P} on a qubitoperator Q and a Pauli operator P.

qop the QubitOperator to be rotated
pauli a single Pauli operator - a QubitOperator with a single term, and a coefficient equal to 1.
angle the angle to be rotated by.

rotated_op - the rotated QubitOperator following the above formula.

TypeError qop must be a QubitOperator
TypeError pauli must be a Pauli Operator (QubitOperator with single term and coefficient equal to 1).