Update dtdesign (vocabularies and descriptions) dependency to include 'flying car' in Docker build.

flake.nix

@@ -154,7 +154,7 @@
             let
               dtdesignRepo = builtins.fetchGit {
                 url = "git@msdl.uantwerpen.be:lucasalbertins/DTDesign.git";
-                rev = "7d30e3b9b5c6202c3fcbf225de3b32fc9b7ac831";
+                rev = "768013a08a353d06c3297b368f71ca02fc3a5b88";
                 ref = "main";
                 shallow = true;
               };