remove duplicated query params

[bwidtmann]

this bug occurs when using new retry feature and using query params in the URL string instead of passing it via the .query({qs: 'present'}) object.

[kornelski]

Do you have an example code showing the bug that happens with retry?

This is supported:

request.get().query('arr[]=1').query('arr[]=1')

So this is a breaking change, and the fix must be different.

[bwidtmann]

request.get('http://www.google.com?bla=1&blup=1).retry(1)

the first request is ok, the second request would be:

http://www.google.com?bla=1&blup=1&bla=1&blup=1

you know what I mean?

[kornelski]

Thanks. I've made a fix for the root cause in #1200