WASHINGTON — Congress sped toward reopening the government today, as Senate Democrats dropped their objections to a temporary funding bill in return for assurances from Republican leaders that they will soon take up immigration and other contentious issues.Senate Republican leader McConnell’s commitment to quickly tackle the issue of immigrant “Dreamers” was contingent on Democrats providing enough votes now for a stopgap spending measure lasting a little less than three weeks. The measure needed 60 votes, and Democrats …