If there’s one thing we can safely predict about the Covid-19 pandemic, it’s that plenty of coronavirus tests lie in our future. Luckily, researchers have some good news.Two new studies have found that tests that look for the virus in samples of saliva are about as reliable as tests that require a sample from the back of the nose.That’s sure to be a welcome development to anyone who would rather avoid the discomfort of having a long, stiff swab inserted so far back into their nasal cavity that…