MANILA, Philippines — Three years after their golden performance at home, Filipino athletes return to action today, competing in the early hostilities ahead of the formal opening of the 31st Southeast Asian Games in Hanoi, Vietnam. The football and beach handball teams and the kickboxers will be the first to go into battle, signaling the start of the Philippines’ title defense in the regional conclave. But even before action unfolds, the Filipinos will have to contend with the COVID-19 threat as three athletes tested positive yesterday, according to Philippine Olympic Committee president Abrah…