Fix track builder spec

spec/services/tracks/track_builder_spec.rb

@@ -323,7 +323,7 @@ RSpec.describe Tracks::TrackBuilder do
       expect(track.user).to eq(user)
       expect(track.points).to match_array(points)
       expect(track.distance).to eq(2000)
-      expect(track.duration).to eq(1.hour.to_i)
+      expect(track.duration).to be_within(1.second).of(1.hour.to_i)
       expect(track.elevation_gain).to eq(20)
     end
   end