Describe the bug
For a CASA image created in CASA with tclean, the "file information" in the "file browser" dialog of CARTA reports the restoring beam position angle to be -1.44 deg while the "header" tab shows BPA = -8.235030409149E+01. Also, the beam ellipse when the image is loaded is using the position angle reported under "file information".

imhead in CASA shows that the position angle is -1.44 radians, so it looks like CARTA is assuming it is in degrees in some places.

To Reproduce

1. Click File -> Open image.
2. Click on the image.
3. Note the restoring beam position angle under "file information".
4. Click the "header" tab and note the different value.
5. Click Load and the beam ellipse is drawn with the "file information" position angle.

Expected behavior
The "file information" should report the correct position angle value with the appropriate units (either report radians like imhead does or convert value to degrees). The beam ellipse should be drawn based on the value and units of the position angle being consistent.

Platform info (please complete the following information):

• OS: MacOS 10.15.7
• Browser: N/A (just running CARTA app directly in it's own window)
• Version: 3.0.0-beta.2b

Additional context
One of my cubes where I am seeing this issue is fairly small (6 MB) and I can provide it if that would help.

Thanks.