Revert "python: pamqp: 2.3.0 -> 3.0.1"

No version of pythonPackages.rabbitpy currently exists that supports 3.0.1

This reverts commit 4250cdeee9.

(cherry picked from commit 178d1b119c)

pkgs/development/python-modules/pamqp/default.nix

@@ -9,12 +9,12 @@
 }:
 
 buildPythonPackage rec {
-  version = "3.0.1";
+  version = "2.3.0";
   pname = "pamqp";
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "0a9b49bde3f554ec49b47ebdb789133979985f24d5f4698935ed589a2d4392a4";
+    sha256 = "1s4lwbsiikz3czqad7jarb7k303q0wamla0rirghvwl9bslgbl2w";
   };
 
   buildInputs = [ mock nose pep8 pylint mccabe ];