fix: support measurements on qubits without gates

Issue #, if available:

Description of changes: Currently, the local simulators do not support measuring qubits that are not used (do not a gate) on the circuit.

Example:

Circuit().measure(0)

Circuit().h(0).cnot(0,1).measure([0, 1, 2])

To support this any qubits that are measured but not used, should return 0

Example:

circ = Circuit().measure(0)
result = device.run(circ, shots=10).result()
print(result.measurements)

[[0]
 [0]
 [0]
 [0]
 [0]
 [0]
 [0]
 [0]
 [0]
 [0]]

circ = Circuit().h(0).cnot(0,1).measure([0, 1, 2])
result = device.run(circ, shots=10).result()
print(result.measurements)

[[1 1 0]
 [1 1 0]
 [0 0 0]
 [1 1 0]
 [1 1 0]
 [1 1 0]
 [0 0 0]
 [0 0 0]
 [1 1 0]
 [0 0 0]]

Testing done: tox

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amazon-braket / amazon-braket-default-simulator-python