Update supported data formats in documentation

[sfinkens]

Add a note that 10 bits/pixel are required.

Closes https://github.com/pytroll/satpy/issues/2494

[sfinkens]

Should we make sure the satpy reader doc states the same?

Good idea! -> https://github.com/pytroll/satpy/pull/2501

[sfinkens]

Should we add a screenshot of the downloading interface here?

Added a screenshot.

[codecov[bot]]

Codecov Report

Merging #123 (d7770f3) into main (748774e) will not change coverage. The diff coverage is n/a.

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##             main     #123   +/-   ##
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  Coverage   74.39%   74.39%           
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  Files          32       32           
  Lines        2882     2882           
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  Hits         2144     2144           
  Misses        738      738