league-of-moveable-type: add league-mono

+1
+1
pkgs/by-name/le/league-of-moveable-type/package.nix
··· 9 junction-font, 10 knewave, 11 league-gothic, 12 league-script-number-one, 13 league-spartan, 14 linden-hill,
··· 9 junction-font, 10 knewave, 11 league-gothic, 12 + league-mono, 13 league-script-number-one, 14 league-spartan, 15 linden-hill,