WASHINGTON – President Donald Trump said Monday the United States has done “too good a job” on testing for cases of COVID-19, even as his staff insisted the president was only joking when he said over the weekend that he had instructed aides to “slow the testing down, please.”The president’s comments at a campaign rally in Tulsa, Oklahoma, on Saturday brought quick rebukes from the campaign of likely Democratic presidential nominee Joe Biden as well as scores of Democratic lawmakers.In an interview with Scripps for its local TV stations, Trump was asked Monday whether he did indeed tell aides to “slow it down.” He did not directly answer the question. “If it did slow down, frankly, I think we’re way ahead of ourselves, if you want to know.