President Donald Trump moved Friday to thin the Republican field running for Senate in Kentucky, endorsing Rep. Andy Barr and prompting businessman Nate Morris — who had support from key Trump world figures — to drop out of the race for retiring Sen. Mitch McConnell's open seat. “I know Andy well, and he is always a Vote we can count on because he knows what it takes to GET THINGS DONE and, MAKE AMERICA GREAT AGAIN!” Trump wrote in a post on his Truth Social site. The post came 16 minutes after Trump wrote that he had met with Morris on Thursday and urged him to end his campaign and instead accept an ambassadorship. “When President Trump asks you to serve your nation, you answer the call,” Morris said in a statement to NBC News, confirming that he has decided to drop out of the race.…