When a cabal file can't be found, warn that extra-deps could be the problem too #3808
Note: Documentation fixes for https://docs.haskellstack.org/en/stable/ should target the "stable" branch, not master.
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…roblem too. * Also: slight refactor to use only `concat` instead of ++ in the error message * Also: mention that a package.yaml file would also be accepted * The code that throws this is only searching for a .cabal file, but it runs hpack on the directory immediately before that to generate a cabal file, so it's effectively looking for a package.yaml file as well Closes #3806