WASHINGTON — If President Joe Biden’s $2 trillion social and environment package was a Broadway show, its seven months on Congress’ stage could qualify it as a hit. But lawmaking isn’t show business, and many Democrats worry that with the curtain falling soon on 2021, time is not their friend. Each passing day threatens to push final action into 2022, an election year when control of Congress will be at stake and lawmakers will become ever more wary of casting tough votes. Democratic Senate Majority Leader Chuck Schumer wants to end his party’s disagreements and finally squeeze the bill through his chamber before Christmas.