If it ain’t broke, why fix it? And it’s quite clear that the U2 Las Vegas Residency at the Sphere is a smashing success. After selling out their initial concert dates in September and October, the band extended their stay through the end of the year. Now, they have extended it again. It was a record-setting and unprecedented launch for the UV Achtung Baby Live. So, the band and venue have added eleven additional dates in January and February. The first 9 shows have been a sold-out success, and have led to the demand for the additional concerts, listed at…