White House press secretary Karine Jean-Pierre weighed in on the federal bribery charges against Sen. Bob Menendez, D-N.J., on Monday, saying it was a "serious matter" but declined to call for his resignation. Jean-Pierre made the comments in response to questions from reporters at Monday's White House press briefing. Multiple prominent Democrats have already called on Menendez to resign, though he brushed off those calls in a Monday press confe…