fluxcd: use writableTmpDirAsHomeHook

pkgs/by-name/fl/fluxcd/package.nix

@@ -5,6 +5,7 @@
   installShellFiles,
   lib,
   stdenv,
+  writableTmpDirAsHomeHook,
 }:
 
 let
@@ -46,11 +47,11 @@ buildGoModule rec {
 
   subPackages = [ "cmd/flux" ];
 
+  nativeBuildInputs = [ installShellFiles ];
+
   # Required to workaround test error:
   #   panic: mkdir /homeless-shelter: permission denied
-  env.HOME = "$TMPDIR";
-
-  nativeBuildInputs = [ installShellFiles ];
+  nativeCheckInputs = [ writableTmpDirAsHomeHook ];
 
   doInstallCheck = true;
   installCheckPhase = ''