!!! flake.nix: update pyk to custom-kcfg-view branch

Author: ehildenb

flake.nix

@@ -18,7 +18,7 @@
       "github:ethereum/legacytests/d7abc42a7b352a7b44b1f66b58aca54e4af6a9d7";
     ethereum-legacytests.flake = false;
     haskell-backend.follows = "k-framework/haskell-backend";
-    pyk.url = "github:runtimeverification/pyk/v0.1.90";
+    pyk.url = "github:runtimeverification/pyk/custom-kcfg-view";
     pyk.inputs.flake-utils.follows = "k-framework/flake-utils";
     pyk.inputs.nixpkgs.follows = "k-framework/nixpkgs";