LAS VEGAS " Henderson police say officers trying to issue a speeding ticket shot and killed a 42-year-old woman who they say took a knife from her ice cream truck and made threatening moves.The woman has been identified as Deshira Selimaj. She died at St. Rose-Siena hospital after the Tuesday afternoon shooting near Sunridge Heights and Pecos Ridge parkways.Police spokesman Todd Rasmussen says a confrontation ensued after the woman's husband, 65-year-old Zyber Selimaj, was stopped in another ice cream truck.The woman arrived with her 7- and 11-year-old sons, and police say she wielded a knife and at one point used …