OTTAWA—Canada’s promised spring supply of COVID-19 vaccines grew Tuesday with millions of additional doses now expected to arrive from three different suppliers before Canada Day. But the news was tempered by ongoing concerns about the Oxford-AstraZeneca vaccine, and signs in much of the country that the pandemic still has a lot more misery to unleash. “We’re entering the final stretch of this crisis,” Prime Minister Justin Trudeau said at a news conference in Ottawa. “We just need to stay strong, a little longer. More and more vaccine doses are coming every week. So there’s reason to be hopeful.” Trudeau said Pfizer and BioNTech will send another five million doses of their mRNA vaccine to Canada in June, bringing their total shipments in the spring to 17.8 million. The company is expected to ship more than one million doses a week in April and May, and more than two million every …