ICE "Unexpected abstract type pack!" triggered on function call with generics

[JohnnyMorganz]

The following code triggers the "Unexpected abstract type pack!" ICE (note that the FFlag LuauReturnAnyInsteadOfICE is disabled)

local function createUseMemo(useValue)
	return function<T...>(createValue: () -> T..., dependencies: any): T...
		local memoizedValue = { createValue() }
	end
end

This can be reproduced using ./luau-analyze --fflags=LuauReturnAnyInsteadOfICE=False