Ensure libausaxs is downloaded when building installers

[klytje]

Description

libausaxs should now be present and included in the installers.

Fixes #3545, needed for #3544

How Has This Been Tested?

The Linux installer has been tested and verified to now include libausaxs. The issue was that libausaxs was previously only being downloaded for test builds, but not for the installers, which were therefore created without it. As functionality was already verified in #2882 and tests are still passing (including the libausaxs test), I don't think we have to do anything further here.

Review Checklist:

Documentation (check at least one)

• There is nothing that needs documenting
• Documentation changes are in this PR
• There is an issue open for the documentation (link?)

Installers

• This will affect the installers, so
  • Linux installer (GH artifact) has been tested (worked)
  • Windows installer (GH artifact) has been tested (installed and worked)
  • MacOSX installer (GH artifact) has been tested (installed and worked)
  • Wheels installer (GH artifact) has been tested (installed and worked)

Licensing (untick if necessary)

• The introduced changes comply with SasView license (BSD 3-Clause)

[krzywon]

For cleanliness, I would suggest this be a separate step in the CI file, not as part of the pip install.

      - name: Fetch AUSAXS C library
        run: |
          python build_tools/get_external_dependencies.py

[jamescrake-merani]

My view is that this should get merged for 6.1.1, but in the long-term its not an ideal solution. Ideally, this should be packaged in PyPi.

I will try to see if I get some time to try this out before my contract ends, but I can't promise anything.

[klytje]

@jamescrake-merani Yes I agree. This PR is only for restoring functionality. Changing to pypi can be done in a future PR. I've started looking at creating a proper python wrapper for libausaxs link, though it won't be done anytime soon.

[klytje]

@krzywon

For cleanliness, I would suggest this be a separate step in the CI file, not as part of the pip install.

      - name: Fetch AUSAXS C library
        run: |
          python build_tools/get_external_dependencies.py

Fixed.

[krzywon]

As noted by @jamescrake-merani, this is a reasonable short-term solution. Once this is on pypi, @klytje, please either let us know, or put in a pull request, that removes this step and adds ausaxs to our requirements file.