Remove format=None and intersect=covers for SDSS SIAP

[stargaser]

• Remove the format=None from SDSS SIAP searches
• Slightly update KNOWN_ISSUES since format=None is no longer needed
• Remove idiosyncratic intersect='covers' from first SDSS image search

Fixes #38

[tomdonaldson]

This looks good to me. We will solve the CI elsewhere.

[bsipocz]

I suppose there was a genuine test failure with this notebook, namely something with the format

https://github.com/NASA-NAVO/navo-workshop/actions/runs/7214917787/job/19658931215#step:5:563

I'll have a look whether changing the minimal pyvo version in the oldest version run will resolve it.

[bsipocz]

Ahh, the format=None default has been added in v1.4.1, so I suppose we infact require that as a minimum now, or I could just update the oldest version run to agree with the check env file that Dave has already updated to 1.4.2