Update guzzlehttp/guzzle from 6.5.2 to 6.5.3

[violinist-bot]

If you have a high test coverage index, and your tests for this pull request are passing, it should be both safe and recommended to merge this update.

Here is a list of changes between the version you use, and the version this pull request updates to:

• aab4ebd8 Prepare release of 6.5.3 (#2613)
• 3325c9d9 [6.5] Install symfony's intl-idn polyfill (#2550)
• 9189d469 Don't use internal functions (#2548)
• 400cefd2 Merge pull request #2518 from GrahamCampbell/patch-1
• 27c81686 Travis improvements
• a7680be7 Fixed deprecation warning in node test server (#2517)

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[coveralls]

Coverage remained the same at 99.038% when pulling 0f5b058 on violinist-dev:guzzlehttpguzzle652653 into b41207e on typhonius:master.