Remove sphinx from native inputs

[jgart]

Hi Goblineers,

I moved sphinx to native inputs since if sphinx were to be used it would be 
used to
build docs instead of as a direct library input to mediagoblin. The patch is 
attached.

Also, propagated-inputs should be changed to inputs.

This is because mediagoblin is an end user application and not a library.

This helps with not polluted your environment.

See jrnl for an example of another python application that does the same:

`guix edit jrnl`

all best,

jgart
 
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0001-Move-python-sphinx-to-native-inputs.patch
Description: Text document