fix: Correct debugging_monitor.py script instructions (#676)

## Summary

**What is the goal of this PR?**
- Minor correction to the `debugging_monitor.py` script instructions

**What changes are included?**
- `pyserial` should be installed, NOT `serial`, which is a [different
lib](https://pypi.org/project/serial/)
- Added macOS serial port

## Additional Context

- Just a minor docs update. I can confirm the debugging script is
working great on macOS

---

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README.md

@@ -102,13 +102,18 @@ After flashing the new features, it’s recommended to capture detailed logs fro
 First, make sure all required Python packages are installed:
 
 ```python
-python3 -m pip install serial colorama matplotlib
+python3 -m pip install pyserial colorama matplotlib
 ```
 after that run the script:
 ```sh
+# For Linux
+# This was tested on Debian and should work on most Linux systems.
 python3 scripts/debugging_monitor.py
+
+# For macOS
+python3 scripts/debugging_monitor.py /dev/cu.usbmodem2101
 ```
-This was tested on Debian and should work on most Linux systems. Minor adjustments may be required for Windows or macOS.
+Minor adjustments may be required for Windows.
 
 ## Internals