Adding fsspec support to `astropy.io.fits`

I'm opening this issue to draw attention to the fact that I opened an Astropy PR today (https://github.com/astropy/astropy/pull/13238) which would add explicit support for opening FITS files with `fsspec`.

This PR may not necessarily benefit `intake-astro`, because I believe this package already makes clever use of AstroPy's lazy data loading features (i.e., `ImageHDU.section` and `lazy_load_hdus=True`).

Perhaps the most important contribution of the Astropy PR, however, is that it adds documentation on the use of `fsspec` with FITS files, aimed at astronomers. For example, the Astropy PR would add a chapter on the use of `fsspec` to the Astropy docs which can be previewed here:

https://astropy--13238.org.readthedocs.build/en/13238/io/fits/usage/cloud.html

/ping @martindurant: I'd be interested to hear your thoughts on the PR. I'm happy to be told this is a bad idea, or have my attention drawn to any incorrect claims I may accidentally have made about fsspec in the Astropy docs.