WASHINGTON — The Biden administration is again making some free COVID-19 tests available to all U.S. households as it unveils its contingency plans for potential coronavirus surges this winter.After a three-month hiatus, the administration is making four rapid virus tests available through covidtests.gov starting Thursday, a senior administration official said. The official spoke on the condition of anonymity to discuss the program. COVID-19 cases have shown a marked increase after the Thanksgiving holiday, and …