Meshtastic Python 2.3.9

What's Changed

• Print 0 for channel rather than N/A, since we should probably always have a channel by @ianmcorvidae in #563
• Fix typo in main.py by @jhollowe in #564
• add a warning on --ch-enable and --ch-disable, which should usually be avoided by @ianmcorvidae in #574

New Contributors

• @jhollowe made their first contribution in #564

Full Changelog: 2.3.8...2.3.9

As with other releases, please install with pip if a standalone binary is unavailable or nonfunctional.