Convert colorspace for actual ethernet cams

In our actual codebase, we use convert the ethernet cams' colorspace to a normal one:

```python
# Switches ethernet's color profile from BayerBGR to BGR
cv_img = cv2.cvtColor(cv_img, cv2.COLOR_BAYER_BGGR2BGR)
```

Right now, the video stream publisher nodes in this bootcamp wouldn't work with that conversion.

Confirm this conversion is necessary and works with the actual ethernet cams (might need `RGGB2BGR` instead?). Then make the video stream publishers use the ethernet cams' colorspace so this conversion can always be applied.

Locate the video stream publisher nodes and inspect how they currently handle camera colorspaces. Verify the Bayer-to-BGR conversion with the actual ethernet cameras, including whether BGGR or RGGB is correct. Done means the publishers consistently use the ethernet cameras' colorspace and the conversion works for their video streams.

Written by the indexing model from the issue text.