Don't decompose clifford rotations

[amandashoe]

For example, rz(pi/2) should be directly translated rather than decomposed.

[amandashoe]

In this file: https://github.com/qqq-wisc/wisq/blob/main/src/wisq/qualtran_rotation_synthesis.py

If the angle is divisible by pi/2, don't call diagonal_unitary_approx. Instead, replace it with the corresponding Clifford circuit by running Qiskit BasisTranslator (https://quantum.cloud.ibm.com/docs/en/api/qiskit/qiskit.transpiler.passes.BasisTranslator#translation-errors)