haskellPackages.dhall-nix{,pkgs}: remove cabal revision pins

We got these cabal file revisions with our hackage update, so we can
remove it from the common configuration file.

pkgs/development/haskell-modules/configuration-common.nix

@@ -943,16 +943,7 @@ self: super: {
   # https://github.com/commercialhaskell/stackage/issues/5795
   # This issue can be mitigated with 'dontCheck' which skips the tests and their compilation.
   dhall-json = generateOptparseApplicativeCompletions ["dhall-to-json" "dhall-to-yaml"] (dontCheck super.dhall-json);
-  # dhall-nix, dhall-nixpkgs: pull updated cabal files with updated bounds.
-  # Remove at next hackage update.
-  dhall-nix = generateOptparseApplicativeCompletion "dhall-to-nix" (overrideCabal super.dhall-nix {
-    revision = "2";
-    editedCabalFile = "1w90jrkzmbv5nasafkkv0kyfmnqkngldx2lr891113h2mqbbr3wx";
-  });
-  dhall-nixpkgs = overrideCabal super.dhall-nixpkgs {
-    revision = "1";
-    editedCabalFile = "1y08jxg51sbxx0i7ra45ii2v81plzf4hssmwlrw35l8n5gib1vcg";
-  };
+  dhall-nix = generateOptparseApplicativeCompletion "dhall-to-nix" super.dhall-nix;
   dhall-yaml = generateOptparseApplicativeCompletions ["dhall-to-yaml-ng" "yaml-to-dhall"] super.dhall-yaml;
 
   # https://github.com/haskell-hvr/netrc/pull/2#issuecomment-469526558