WASHINGTON — America's top diplomat is again urging India and Canada to work together on bringing Hardeep Singh Nijjar's killers to justice — and hopefully forestall a deepening of a serious geopolitical rift between two important allies. U.S. Secretary of State Antony Blinken said he delivered that message Thursday during his meeting in Washington, D.C., with Subrahmanyam Jaishankar, India's external affairs minister. Relations between Canada and India have plumbed new depths since Prime Minist