Build.hs: Drop redundant dependency on System.Nix.Path

Author: shlevy

hnix-store-core/src/System/Nix/Build.hs

@@ -12,7 +12,6 @@ module System.Nix.Build (
 
 import           Data.Text                 (Text)
 import           Data.HashSet              (HashSet)
-import           System.Nix.Path           (Path)
 
 data BuildMode = Normal | Repair | Check
   deriving (Eq, Ord, Enum, Show)