helics_connector JSON matchfile not working

[trevorhardy]

Describe the bug
Using the JSON format for the helics_connector matchfile does not produce matches

What is the expected behavior?
JSON matchfile would work

To Reproduce
Run advanced User Guide example:
`helics run --path=./connector_matchfile_direct_runner.json

Look at helics_connector.log

[2025-01-10 17:40:54.757] [console] [info] connector (131072)[created]::0 connections made

Environment (please complete the following information):

• Operating System: Mac
• Language Extension: Python
• what compiler or setup process did you use: pip install helics helics_apps
• HELICS version:

$ helics --version
helics, version 3.6.0

Python HELICS version 3.6.0

HELICS Library version 3.6.0 (2024-12-09)

Here's the JSON matchfile ("direct_matchfile.json"):

{
  "connections": [
  ["Charger/EV1_output_voltage", "Battery/EV1_input_voltage", "from_to"],
  ["Charger/EV2_output_voltage", "Battery/EV2_input_voltage", "from_to"],
  ["Charger/EV3_output_voltage", "Battery/EV3_input_voltage", "from_to"],
  ["Charger/EV4_output_voltage", "Battery/EV4_input_voltage", "from_to"],
  ["Charger/EV5_output_voltage", "Battery/EV5_input_voltage", "from_to"],
  ["Charger/EV1_input_current", "Battery/EV1_output_current", "to_from"],
  ["Charger/EV2_input_current", "Battery/EV2_output_current", "to_from"],
  ["Charger/EV3_input_current", "Battery/EV3_output_current", "to_from"],
  ["Charger/EV4_input_current", "Battery/EV4_output_current", "to_from"],
  ["Charger/EV5_input_current", "Battery/EV5_output_current", "to_from"]
  ]
}