LISBON (Reuters) – Portugal’s No. 2 retailer Jeronimo Martins on Thursday posted a 52% jump in first-quarter net income as its key market Poland led a rise in sales, but warned of uncertainty ahead due to the conflict in Ukraine, inflation and other factors. The company booked a net profit of 88 million euros ($92.35 million) between January and March, up from 58 million euros a year earlier, when it was marked by the COVID-19 pandemic and also included the Easter holiday season. “Significant uncertainty prevails, linked to the developments of the war in Ukraine and the evolution of the COVID-…