NEW YORK — ‘Tis the season for COVID-19 and the flu. New York City Health officials reported holiday spikes in both ailments and other seasonal illnesses Saturday while urging New Yorkers to take precautions as Christmas and New Year’s Day approach. The uptick includes both an increase in cases and hospitalizations, with the department issuing a health advisory. “The holiday season is about togetherness and there is a way to gather safely — even as respiratory viruses in our city are unusually high,” said city Health Commissioner Dr. Ashwin Vasan. “We want everyone to have a happy — and most o…