pin version of faraday (imported by octokit) to 0.17.3. There is a build error...

pin version of faraday (imported by octokit) to 0.17.3. There is a build error when faraday version 1.0 is used.

revert this fix when octokit imports a different version or patches faraday.
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Status Job ID Name Coverage
  Build
passed #12901
build

00:00:50

 
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restricted
deploy

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