appveyor:  try to reduce 'stack setup' noise
appveyor:  try to reduce 'stack setup' noise

This follows best practices[1] on making stack setup stop killing everyone's machines on Appveyor.

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1. https://github.com/commercialhaskell/stack/blob/master/appveyor.yml#L20

input-output-hk/daedalus,input-output-hk/daedalus,input-output-hk/daedalus,input-output-hk/daedalus,input-output-hk/daedalus,input-output-hk/daedalus