Update flow-bin to the latest version � (#763)

Summary:
## The devDependency [flow-bin](https://github.com/flowtype/flow-bin) was updated from `0.115.0` to `0.117.0`.
This version is **not covered** by your **current version range**.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

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**Publisher:** [mvitousek](https://www.npmjs.com/~mvitousek)
**License:** MIT

[Find out more about this release](https://github.com/flowtype/flow-bin).

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<details>
  <summary>FAQ and help</summary>

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Your [Greenkeeper](https://greenkeeper.io) bot 🌴
Pull Request resolved: https://github.com/facebook/flipper/pull/763

Reviewed By: passy

Differential Revision: D19621269

Pulled By: mweststrate

fbshipit-source-id: d213eeda19ba3715471f3843b38a8ae5d7a53713

package.json

@@ -100,7 +100,7 @@
     "eslint-plugin-prettier": "^3.1.2",
     "eslint-plugin-react": "^7.16.0",
     "eslint-plugin-relay": "^1.4.1",
-    "flow-bin": "0.115.0",
+    "flow-bin": "0.117.0",
     "glob": "^7.1.2",
     "jest": "^24.7.1",
     "jest-fetch-mock": "^3.0.0",