Refactor lowering list of qubits (gate operands) in syntax_to_semantics.rs

[jlapeyre]

Code like this:

openqasm3_parser/crates/oq3_semantics/src/syntax_to_semantics.rs

Lines 393 to 397 in dac0d7a

	let gate_operands = barrier.qubit_list().map(|operands| {
	operands
	.gate_operands()
	.map(|qubit| from_gate_operand(qubit, context))
	.collect()

is repeated in several places. It should be factored into a function from_qubit_list or ast_from_qubit_list.

[abhamra]

I can work on this issue as well!

[atomgardner]

Dear @jlapeyre, could you please assign this issue to me so the UF robot can assign credit.