SONIA ELKS GET a COVID-19 jab in California and you could walk away with a lot more than a sore arm - a $1.5 million lottery jackpot is up for grabs for residents of the state who get vaccinated. From dollars to donuts, a dizzying array of incentives are being offered by authorities and companies around the world in a bid to win around the vaccine hesitant as they seek to turn a page on the pandemic. But as countries strive to reach 'herd immunity' - where enough people are protected against a disease that it becomes  difficult for infections…