Bugfix parameter unpacking in gate_factory

[MSRudolph]

Description

The function would break if the passed parameters are a 1d array. parameter would then be a float.

@roberCO found this bug in z-quantum-core. I thought I once made a PR about this, but apparently it was never merged.

Please verify that you have completed the following steps

• [yes] I have self-reviewed my code.
• [no] I have included test cases validating introduced feature/fix.
• [no] I have updated documentation.

[AthenaCaesura]

Can we add a test case where the user passes parameters with the wrong shape and ensures that an error is thrown? Just in case we refactor and this check gets deleted for some reason.

[AthenaCaesura]

On second thought, this is not a bug this is a feature. You are supposed to provide an numpy array of parameters when you call this function. Is there a problem with this? If not, then I'm going to close this issue.

[MSRudolph]

See this PR where it was seen as a bug:
zapatacomputing/z-quantum-core#486

from orquestra.quantum.circuits import Circuit, RX, apply_gate_to_qubits
apply_gate_to_qubits(Circuit(), (0, 1), RX, np.array([1, 2]))

parameters should be a np.ndarray, but when you iterate over its elements, it may break. Am I understanding the purpose of this function incorrectly?