python310Packages.imutils: opencv3 -> opencv4

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

···
 { lib
 , buildPythonPackage
 , fetchPypi
-, opencv3
+, opencv4
 }:
 
 buildPythonPackage rec {
···
     sha256 = "03827a9fca8b5c540305c0844a62591cf35a0caec199cb0f2f0a4a0fb15d8f24";
   };
 
-  propagatedBuildInputs = [ opencv3 ];
+  propagatedBuildInputs = [ opencv4 ];
 
   # no tests
   doCheck = false;