Cleanup unused packages

Author: LaurentRDC

pandoc-plot.cabal

@@ -122,8 +122,6 @@ library
         , typed-process      >= 0.2.1 && < 1
         , yaml               >= 0.8   && < 1
         , mtl                >= 2.2   && < 3
-    if !os(windows)
-        build-depends:  unix >= 2.4 && < 2.9
     default-language: Haskell2010
 
 executable pandoc-plot
@@ -138,7 +136,6 @@ executable pandoc-plot
     ghc-options: -Wall -Wcompat -threaded -rtsopts -with-rtsopts=-N
     build-depends:
           base                  >= 4.11 && <5
-        , containers
         , directory
         , filepath
         , gitrev                >= 1    && < 2