Refactor cubeviz parser and plugins for specutils 2.0 compatibility

[rosteen]

Tests are expected to fail on this, since it requires specutils v2.0-dev and the glue-astronomy compatibility PR to work. But I'd like to get this in front of other people for testing sooner rather than later.

Current known to-do items, I will add to these as new issues they are discovered and update when fixed:

• [x] Deprecate _parse_jwst_s3d now that specutils and glue-astronomy handle GWCS.
• [x] Test JWST ESA 3d file to see if _parse_esa_s3d can be offloaded to Spectrum1D.read like _parse_jwst_s3d was.
• [x] Fix slice plugin getting values from wrong axis.
• [x] Fix coords info showing 0 or NaN for the value on hover.
• [ ] Verify that coords_info is giving flux for correct pixel.
• [x] Spectral extraction is failing with an error in the glue-astronomy NDData translator.
• [x] Aperture photometry fails due to attempting to operate on the wrong axis.

[rosteen]

I confirmed offline that the ESA parser can be removed, it was specifically to support commissioning.

[rosteen]

It looks like the pixel coords_info is returning a value for is off by one in the y-direction, not immediately obvious to me why (I don't think GWCS is 1-indexed...).