MILAN/HONG KONG—Stock markets in Europe and Asia cemented gains in light holiday trade on Friday, while the safe-haven dollar eased on signs the Omicron variant would not significantly derail global economic growth. The greenback was set for its worst week in four months while other risk-friendly assets from bitcoin to the Australian dollar held onto their recent gains, buoyed by ebbing concerns over the severity of the new COVID-19 variant. A top European equity benchmark hovered around one month highs after a week of gains and the MSCI’s broadest index of Asia-Pacific shares outside Japan added 0.1 percent, after a record closing high for S&P 500 on Thursday. Even though it is highly infectious, studies have shown how Omicron is less severe than the Delta strain, fuelling optimism about a limited fallout from new restrictions, and setting the MSCI world equity index for a 2 percent weekly gain. “The most …