From left, Dale Monroe, Tony Knotts and Michael Gardiner co-star in Hudson Theatre Works’ production of Eugene O’Neill’s “Desire Under the Elms.” For fans of serious theater on an affordable budget, the Hudson Theatre Works’ Eugene O’Neill Festival — presenting two plays for one low price — couldn’t come at a better time. Especially for those looking to return to live theater after a long drought caused by the pandemic. Presented in the auditorium of the Woodrow Wilson School in Weehawken, the festival features one of O’Neill’s best-known works, “Desire Under the Elms,” along with the lesser k…