feat: Track classical register indices for measurements

[Altanali]

Issue #, if available:
#1004

Description of changes:
Update the BraketProgramContext to extend the changes introduced in amazon-braket/amazon-braket-default-simulator-python#266, which provide a classical register index to the BraketProgramContext add_measure method when a measurement assignment is used in an OpenQASM program (e.g. b[1] = measure q[1];). This allows translations to and from Braket BDK Circuits and OpenQASM to be consistent with regards to classical register indices used in measurement assignments as currently, these indices are discarded entirely.

Additionally, updating the _measure_targets array in the Circuit object was moved to the add_instruction method from the _add_measure method. This is because users of the Circuit class are able to add measurement instructions via the add_instruction method, but _measure_targets will not be updated to reflect qubits used in the measurement. This results in incorrect behavior when using to_ir to take a circuit with measurements added via add_instruction method calls to OpenQASM as to_ir will check the _measure_targets variable to see if any qubits are measured, see that the list is empty, and apply a measurement to all the qubits in the circuit, including those already measured via the original add_instruction method calls.

Testing done:

A round trip test was added to verify that classical register assignments are persisted when going from BDK Circuit to OpenQASM and back to BDK Circuit via the to_ir and from_ir methods; this is similarly checked when going from OpenQASM to BDK Circuit back to OpenQASM.

Merge Checklist

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[speller26]

How to get around breaking dependencies:

1. Remove this test from this PR and revert the versions in setup.py and tox.ini
2. Merge this PR
3. Merge feat: Track classical register indices for measurements amazon-braket-default-simulator-python#266
4. Create and merge new PR that reintroduces this test and bumps the default simulator version in setup.py to latest release

Suggested change

	def test_from_ir_round_trip_transformation_with_targeted_measurements():
	circuit = (
	Circuit()
	.h(0)
	.cnot(0, 1)
	.add_instruction(Instruction(Measure(index=2), 1))
	.add_instruction(Instruction(Measure(index=1), 2))
	.add_instruction(Instruction(Measure(index=0), 0))
	)
	ir = OpenQasmProgram(
	source="\n".join(
	[
	"OPENQASM 3.0;",
	"bit[3] b;",
	"qubit[3] q;",
	"h q[0];",
	"cnot q[0], q[1];",
	"b[2] = measure q[1];",
	"b[1] = measure q[2];",
	"b[0] = measure q[0];",
	]
	),
	inputs={},
	)
	assert Circuit.from_ir(ir) == Circuit.from_ir(circuit.to_ir("OPENQASM"))
	assert circuit.to_ir("OPENQASM") == Circuit.from_ir(ir).to_ir("OPENQASM")

[Altanali]

I've removed the test and reverted the targets for the default simulator version in the setup.py and tox.ini files in the following commit: 7b3ebf3 !