WASHINGTON — The Supreme Court on Monday narrowed the reach of a federal law that strengthens penalties for career criminals found to illegally have a gun.The high court was ruling in the case of a man a lower court classified as a career criminal after counting the man’s burglary of 10 different public storage units on a single evening as 10 separate offenses. The high court said unanimously Monday that was an error.The man’s 10 burglary convictions should have been treated as one event rather than …