By Jeff Mason WASHINGTON (Reuters) -U.S. households can order four free at-home COVID-19 tests from the government website COVIDTests.gov beginning on Thursday as part of the Biden administration’s efforts to tackle coronavirus infections over the winter. The White House said it would use existing funding to pay for the tests since it has been unsuccessful so far in getting Congress to pass a bill to put more money toward the U.S. COVID-19 response. The free tests program was paused because officials wanted to make sure there were enough tests available for a likely spike in COVID cases in the…