The ONEFlight Myrtle Beach Classic just got an interesting addition to the field.  Brooks Koepka has committed to the PGA Tour opposite-field event next week, which will be played against the Truist Championship, a signature event.  The five-time major champion left LIV Golf in December and was brought back to the PGA Tour under a newly created returning member program. One of the stipulations of Koepka’s reinstatement was that he could not receive sponsor exemptions into signature events; he can only play them if he qualifies.  The 35-year-old was the first alternate for the signature RBC Heritage two weeks ago, but did not get into the field.  Koepka has made eight starts this year, with three missed cuts and four top 20s. He recently placed T12 at the Masters and is second on Tour in strokes-gained approach.  The Myrtle Beach Classic leads into the PGA Championship at Aronimink Golf Club outside of Philadelphia.…