TST: Grab dev spectral-cube and radio-beam to fix devdeps

[pllim]

Description

We still cannot escape having to install spectral-cube because of glue-viz/glue-astronomy#62 . So we need:

• MNT: Clean up _astropy_init.py radio-astro-tools/spectral-cube#891 and
• Clean up _astropy_init.py radio-astro-tools/radio-beam#116

to be released upstream.

Example failure: https://github.com/spacetelescope/jdaviz/actions/runs/6500257549/job/17655283046

Change log entry

• Is a change log needed? If yes, is it added to CHANGES.rst? If you want to avoid merge conflicts,
  list the proposed change log here for review and add to CHANGES.rst before merge. If no, maintainer
  should add a no-changelog-entry-needed label.

Checklist for package maintainer(s)

This checklist is meant to remind the package maintainer(s) who will review this pull request of some common things to look for. This list is not exhaustive.

• Are two approvals required? Branch protection rule does not check for the second approval. If a second approval is not necessary, please apply the trivial label.
• Do the proposed changes actually accomplish desired goals? Also manually run the affected example notebooks, if necessary.
• Do the proposed changes follow the STScI Style Guides?
• Are tests added/updated as required? If so, do they follow the STScI Style Guides?
• Are docs added/updated as required? If so, do they follow the STScI Style Guides?
• Did the CI pass? If not, are the failures related?
• Is a milestone set? Set this to bugfix milestone if this is a bug fix and needs to be released ASAP; otherwise, set this to the next major release milestone.
• After merge, any internal documentations need updating (e.g., JIRA, Innerspace)?

[codecov]

Codecov Report

All modified lines are covered by tests ✅

📢 Thoughts on this report? Let us know!.

[pllim]

radio_beam/_astropy_init.py

[pllim]

Well that is annoying. I cannot make spectral-cube disappear either. So the only thing left to do is to also wait for radio-beam to get patched. 😿