emacsPackages.gnuplot-mode: replace program (#343482)

        forge = buildWithGit super.forge;

        gnuplot-mode = super.gnuplot-mode.overrideAttrs (attrs: {

          postPatch = attrs.postPatch or "" + ''

            substituteInPlace gnuplot-mode.el \

              --replace-fail 'gnuplot-program "gnuplot"' 'gnuplot-program "${lib.getExe pkgs.gnuplot}"'

          '';

        });

        magit = buildWithGit super.magit;

        magit-find-file = buildWithGit super.magit-find-file;