New Jersey on Sunday reported another 21 confirmed COVID-19 deaths and 2,603 cases, the fewest single-day case total since Dec. 6, marking another promising sign the omicron variant may be waning. The number of cases reported Sunday represents a steep 92% decrease from this month’s high of 33,459 in the midst of the omicron surge, but the decline is also likely due in part to a decrease in testing on account of the winter storm. The state’s seven-day average for new confirmed positive tests fell to 5,370, down 42% from a week ago and 67% from a month ago as the recent wave driven by the omicro…