Suggestion: depend on astropy-base instead of astropy

[regro-cf-autotick-bot]

I noticed that this recipe depends on astropy instead of astropy-base. The astropy feedstock has been split into two packages, astropy-base only has required dependencies and astropy now has all optional dependencies. To maintain the old behavior you should migrate to astropy-base. Thus I made this PR.

Notes and instructions for merging this PR:

1. Make sure that the recipe can indeed only depend on astropy-base.
2. Please merge the PR only after the tests have passed.
3. Feel free to push to the bot's branch to update this PR if needed.

If this PR was opened in error or needs to be updated please add the bot-rerun label to this PR. The bot will close this PR and schedule another one. If you do not have permissions to add this label, you can use the phrase @conda-forge-admin, please rerun bot in a PR comment to have the conda-forge-admin add it for you.

_{This PR was created by the regro-cf-autotick-bot. The regro-cf-autotick-bot is a service to automatically track the dependency graph, migrate packages, and propose package version updates for conda-forge. Feel free to drop us a line if there are any issues! This PR was generated by https://github.com/regro/cf-scripts/actions/runs/12170694456 - please use this URL for debugging.}

[conda-forge-admin]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe/meta.yaml) and found it was in an excellent condition.

I do have some suggestions for making it better though...

For recipe/meta.yaml:

• ℹ️ PyPI default URL is now pypi.org, and not pypi.io. You may want to update the default source url.

_{This message was generated by GitHub Actions workflow run https://github.com/conda-forge/conda-forge-webservices/actions/runs/12171055419. Examine the logs at this URL for more detail.}

[MarkWieczorek]

@conda-forge-admin please rerender

[conda-forge-admin]

Hi! This is the friendly automated conda-forge-webservice.

I tried to rerender for you, but it looks like there was nothing to do.

_{This message was generated by GitHub Actions workflow run https://github.com/conda-forge/conda-forge-webservices/actions/runs/12275558358. Examine the logs at this URL for more detail.}

[MarkWieczorek]

The osx ARM64 builds are failing because meson can't find BLAS. Does anyone have any ideas on how to fix this? Maybe @jan-janssen ?

meson.build:15:9: ERROR: Dependency lookup for BLAS with method 'pkgconfig' failed: Pkg-config for machine host machine not found. Giving up.