certbot: 2.4.0 -> 2.6.0

Also add setuptools because certbot imports the `pkg_resources`
module that is found in there.

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

@@ -17,6 +17,7 @@
 , six
 , zope-component
 , zope_interface
+, setuptools
 , dialog
 , gnureadline
 , pytest-xdist
@@ -26,13 +27,13 @@
 
 buildPythonPackage rec {
   pname = "certbot";
-  version = "2.4.0";
+  version = "2.6.0";
 
   src = fetchFromGitHub {
     owner = pname;
     repo = pname;
     rev = "refs/tags/v${version}";
-    hash = "sha256-BQsdhlYABZtz5+SORiCVnWMZdMmiWGM9W1YLqObyFo8=";
+    hash = "sha256-CbYamk1+NvcyS6w7pOjpD5lqWHCk+VJqF9R3xYxzpQk=";
   };
 
   sourceRoot = "${src.name}/${pname}";
@@ -52,6 +53,7 @@ buildPythonPackage rec {
     six
     zope-component
     zope_interface
+    setuptools # for pkg_resources
   ];
 
   buildInputs = [ dialog gnureadline ];