By Natalia Zinets LVIV, Ukraine (Reuters) – Rockets struck the outskirts of the western Ukrainian city of Lviv on Saturday for what appeared to be the first time since Russia’s invasion, and Russian forces took control of a town where workers at the defunct Chernobyl nuclear plant live. Intense fighting raged in several parts of Ukraine, suggesting there will be no swift let-up in the month-old war, and U.S. President Joe Biden called Russian President Vladimir Putin a “butcher” after meeting Ukrainian refugees in Poland. The Kremlin was cited by Russia’s TASS news agency as saying such commen…