added qasm3 benchmark sample

OPENQASM 3;

const nb_steps = 100;

const nb_qubits = 50;

const step_size = 0.01;

const Jz = 1.0;

const h = 1.0;

qubit r[nb_qubits];

// -h*sigma_x layers

for i in [0:nb_steps] {

  rx(-h * step_size) r[i];

}

// -Jz*sigma_z*sigma_z layers

for i in [0:nb_steps - 1] {

  cx r[i], r[i+1];

  rz(-Jz * step_size) r[i + 1];

  cx r[i], r[i+1];

}

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