A federal judge on Monday warned Justice Department lawyers of "serious consequences" if the Trump administration begins major work at a public golf course in the District of Columbia without getting approval and notifying the court in advance.  During a tense conference on Monday morning, U.S. District Judge Ana Reyes demanded she be updated if work begins at the East Potomac Golf Course, and raised concerns about claims made by the Trump administration regarding the state of the course.  "Let's just say, given some issues around the district recently, I would have a particular concern that we not ask first and ask forgiveness later, because that's not going to be acceptable," she said.  Concerns arose in December that the administration may try to take over the course as part of President Donald Trump's efforts to leave his imprint on various D.C. buildings, after the administration terminated the lease of the group that runs the course.…