Josh Duggar will get quite the fiesta behind bars on this birthday because the prison where the former reality star-turned-convicted criminal is serving his 12-year sentence is having tacos for dinner on March 3, RadarOnline.com can reveal. Duggar will turn 36 on Sunday, marking his second birthday while in custody at FCI Seagoville. RadarOnline.com obtained the FederalBureau of Prisons meal schedule, revealing that Duggar and his penitentiary pals will chow down on breakfast for lunch before eating the prison’s version of Mexican food later that night. According to the documents, the incarcer…