Tesla Inc. TSLA, -1.85% has told employees at its California car plant that it plans to boost wages across its U.S. factories in what the electric-vehicle maker described as a “market adjustment pay increase,” Bloomberg reported Thursday. The announcement was posted on a poster at Tesla’s facility in Fremont, California and seen by Bloomberg, the news service said. The company did not comment, the report said. Tesla’s stock was down 1.3% in premarket trading. ...