Reference magnitude does not get passed to pulse info of long square pulses

@djweigand This is the issue brought up in yesterday's meeting.

Description

Execute a long square pulse with a nonzero reference_magnitude on the ComponentBackend Qblox .

What I Did

I've added a minimal example below

Click to show minimal example

from quantify_scheduler.operations import pulse_library
from quantify_scheduler.schedules.schedule import Schedule
from quantify_scheduler.backends.graph_compilation import SerialCompiler
from quantify_scheduler.device_under_test.quantum_device import QuantumDevice
from quantify_scheduler.device_under_test.transmon_element import BasicTransmonElement

quantum_device = QuantumDevice("dummy")
q0 = BasicTransmonElement("q0")
quantum_device.add_element(q0)
cfg = {
    "backend": "quantify_scheduler.backends.qblox_backend.hardware_compile",
    "cluster0": {
        "sequence_to_file": False,
        "ref": "internal",
        "instrument_type": "Cluster",
        "cluster0_module6": {
            "instrument_type": "QCM_RF",
            "complex_output_0": {
                "line_gain_db": 0,
                "portclock_configs": [
                    {"port": "q0:mw", "clock": "q0.01", "interm_freq": -1e8}
                ],
            },
        },
    },
}
quantum_device.hardware_config(cfg)

### Schedule
q0.clock_freqs.f01(4e9)
sched = Schedule("dummy schedule")
sched.add(pulse_library.SquarePulse(
    amp=0.1,
    duration=10e-6,
    port="q0:mw",
    clock="q0.01",
    reference_magnitude=-20
))

compiler = SerialCompiler("dummy", quantum_device)

compiled_sched = compiler.compile(sched)
compiled_sched.operations

What Was Expected

I expected the StitchedPulse operation to have a reference_magnitude entry in the pulse_info dict.

What Actually Happened

This entry was not present.

Note that running

from quantify_scheduler.backends.qblox import constants
constants.PULSE_STITCHING_DURATION = 20e-6

compiler = SerialCompiler("dummy", quantum_device)
compiled_sched = compiler.compile(sched)

compiled_sched.operations

is a temporary fix for this issue, but does not benefit from the stitched pulse benefits.

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