Try to fix js-template-haskell test

Author: hamishmack

overlays/haskell.nix

@@ -782,6 +782,9 @@ final: prev: {
                         "ghc-bignum"]
                       ++ final.lib.optionals (builtins.compareVersions config.compiler.version "9.9" >= 0) [
                         "ghc-internal"]
+                      ++ final.lib.optionals (pkgs.stdenv.hostPlatform.isGhcjs) ([
+                        # ghci and its dependencies
+                        "ghci" "binary" "bytestring" "containers" "template-haskell" "array" "deepseq" "filepath" "ghc-boot" "ghc-boot-th" "ghc-heap" "transformers" "unix" "directory" "time" "ghc-platform" "os-string"]
                       ++ final.lib.optionals (builtins.compareVersions config.compiler.version "8.11" < 0) [
                         "ghcjs-prim" "ghcjs-th"]);
                     })

test/js-template-haskell/default.nix

@@ -10,6 +10,7 @@ let
     cabalProjectLocal = ''
       if arch(javascript)
         extra-packages: ghci
+        constraints: ghcjs installed
       constraints: text -simdutf, text source
     '';
   };