uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/development/python-modules/debtcollector/tests.nix

@@ -0,0 +1,29 @@
+{ buildPythonPackage
+, debtcollector
+, stestr
+}:
+
+buildPythonPackage rec {
+  pname = "debtcollector-tests";
+  inherit (debtcollector) version;
+
+  src = debtcollector.src;
+
+  postPatch = ''
+    # only a small portion of the listed packages are actually needed for running the tests
+    # so instead of removing them one by one remove everything
+    rm test-requirements.txt
+  '';
+
+  dontBuild = true;
+  dontInstall = true;
+
+  checkInputs = [
+    debtcollector
+    stestr
+  ];
+
+  checkPhase = ''
+    stestr run
+  '';
+}