Russia’s invasion of Ukraine appears to be having an unanticipated impact in cyberspace — a decrease in the number of ransomware attacks.  “We have seen a recent decline since the Ukrainian invasion,” Rob Joyce, the U.S. National Security Agency’s director of cybersecurity, told a virtual forum Wednesday.  Joyce said one reason for the decrease in ransomware attacks since the February 24 invasion is likely improved awareness and defensive measures by U.S. businesses.  He also said some of it is tied to measures the United States and its Western allies have …