Fix premature redirect when used with express-session

[zypA13510]

jaredhanson/passport#680

[coveralls]

Pull Request Test Coverage Report for Build 10

• 6 of 8 (75.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.6%) to 95.974%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
lib/middleware/authenticate.js	6	8	75.0%
<!--	Total:	6	8	75.0%	-->

Totals
Change from base Build 9:	-0.6%
Covered Lines:	353
Relevant Lines:	359

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💛 - Coveralls

[rwky]

Note to @passport-next/developers add tests.

[rwky]

@guyellis just wondering if you have time to look at this? If not I'll sort it.

[guyellis]

@rwky probably not this week. I'll see how my time availability pans out later.