By Erwin Seba BEAUMONT, Texas (Reuters) -Union workers approved on Saturday a return-to-work agreement that clears the way for Exxon Mobil Corp to end a 10-month lockout at a southeast Texas refinery, a union official said. The agreement sets the terms for about 600 members of United Steelworkers union (USW) Local 13-243 who Exxon locked out of the Beaumont, Texas, refinery on May 1, 2021, to return to their jobs as early as March 7, said USW international representative Bryan Gross, following the vote. “It’s been a long fight,” Gross said. “It’s finally coming to an end. It’s not where we wan…