Eight months after Kevin Costner’s ex-wife Christine Baumgartner announced her engagement to Josh Conner, the Yellowstone alum is reportedly dating director Kelly Noonan Gores.  Kevin Costner is getting back on the saddle.  Over a year after he legally ended his 18-year marriage to Christine Baumgartner, the Yellowstone alum is casually dating director Kelly Noonan Gores,…