utox: Fixed test configuration

Moved 'check' to nativeBuildInputs, as it is only used by the tests

pkgs/applications/networking/instant-messengers/utox/default.nix

@@ -16,11 +16,11 @@ stdenv.mkDerivation rec {
   buildInputs = [
     libtoxcore dbus libvpx libX11 openal freetype
     libv4l libXrender fontconfig libXext libXft filter-audio
-    libsodium libopus check
+    libsodium libopus
   ];
 
   nativeBuildInputs = [
-    cmake git pkgconfig
+    cmake git pkgconfig check
   ];
 
   cmakeFlags = [
@@ -29,6 +29,8 @@ stdenv.mkDerivation rec {
 
   doCheck = false;
 
+  checkTarget = "test";
+
   meta = with stdenv.lib; {
     description = "Lightweight Tox client";
     homepage = https://github.com/uTox/uTox;