While known as a singular performer – even his stage name is one word – Sting’s next album is a collection of (mostly) previously released collaborations with other artists. But don’t expect Duets to be a simple compilation of hits: only three of these tracks are from the former Police frontman’s studio albums (four, if you count deluxe editions). Everything else is from Sting’s guest appearances on albums by others and the occasional soundtrack appearance. Highlights include his 1999 hit “Desert Rose,” recorded with Algerian rai singer Cheb Mami; “Don’t Make Me…