pythonPackages.ssdeep: Mark broken

https://hydra.nixos.org/build/59943791

This package is a library and has no reverse dependencies. (It was once
used by diffoscope, but it changed to use a different library).

pkgs/top-level/python-packages.nix

@@ -8023,6 +8023,7 @@ in {
 
     buildInputs = with pkgs; [ ssdeep ];
     propagatedBuildInputs = with self; [ cffi six ];
+    meta.broken = true; # Tests fail, and no reverse-dependencies anyway
   };