doppler: fix build failure with shell completion (#326008)

Sets the HOME environment variable to a temporary dir, as the cli attempts to run a setup routine which creates a directory under the user's home

Fixes #325915

also fix cross-compilation

pkgs/by-name/do/doppler/package.nix

@@ -4,6 +4,7 @@
 , installShellFiles
 , lib
 , testers
+, stdenv
 }:
 
 buildGoModule rec {
@@ -28,6 +29,9 @@ buildGoModule rec {
 
   postInstall = ''
     mv $out/bin/cli $out/bin/doppler
+  '' + lib.optionalString (stdenv.buildPlatform.canExecute stdenv.hostPlatform) ''
+    export HOME=$TMPDIR
+    mkdir $HOME/.doppler # to avoid race conditions below
     installShellCompletion --cmd doppler \
       --bash <($out/bin/doppler completion bash) \
       --fish <($out/bin/doppler completion fish) \