Massachusetts tiny corporations grappling with the economic repercussions of the ongoing COVID-19 pandemic can now use for grants up to $75,000, Gov. Charlie Baker said Wednesday as he declared a new round of funding for a application that launched all through last winter’s virus surge just before vaccines turned broadly obtainable. Baker mentioned there’s $50 million available — sourced by federal COVID reduction pounds and appropriated by the Legislature — for modest small business that achieve “socially and economically disadvantaged and traditionally underrepresented groups,” which include business owned by minorities, women, veterans, individuals with disabilities and users of the LGBTQ group. A different $25 million is earmarked for firms that…