Do you know why McCain was ahead of Obama right now in 2008? Clinton supporters who claimed they'd refuse to vote for Obama, because the primary was ongoing.
Do you know why aggregate models have
Clinton ahead by just 3 points? Because of Bernie supporters who claim they'll refuse to vote for Clinton, because the primary season is (in their minds) still ongoing.
She will be fine.
PS: that link shows this isn't even close to the tightest moment between them; see August 22, September 5th, October 3rd, November 18th, January 6th & 7th. There was an August 2015 poll with Trump up by 8 over Clinton - and look what came of that.