Merge #4174

4174: fix hydra caching r=disassembler a=cleverca22

## Description

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## Linked issue

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Co-authored-by: Michael Bishop <[email protected]>

Author: iohk-bors[bot]

default.nix

@@ -44,7 +44,7 @@ let
 in
 { system ? builtins.currentSystem
 , crossSystem ? null
-, config ? {}  # The nixpkgs configuration file
+, config ? import ./nix/config.nix  # The nixpkgs configuration file
 
 # Use a pinned version nixpkgs.
 , pkgs ? localLib.importPkgs { inherit system crossSystem config; }