An in-range update of grpc is breaking the build 🚨

## The dependency [grpc](https://github.com/grpc/grpc-node) was updated from `1.22.1` to `1.22.2`.

🚨 [View failing branch](https://github.com/konsumer/grpcnode/compare/master...konsumer:greenkeeper%2Fgrpc-1.22.2).

This version is **covered** by your **current version range** and after updating it in your project **the build failed**.

grpc is a direct dependency of this project, and **it is very likely causing it to break**. If other packages depend on yours, this update is probably also breaking those in turn.

Status Details

- ❌ **continuous-integration/travis-ci/push:** The Travis CI build could not complete due to an error ([Details](https://travis-ci.org/konsumer/grpcnode/builds/569179268?utm_source=github_status&utm_medium=notification)).

---

FAQ and help

There is a collection of [frequently asked questions](https://greenkeeper.io/faq.html). If those don’t help, you can always [ask the humans behind Greenkeeper](https://github.com/greenkeeperio/greenkeeper/issues/new).

---

Your [Greenkeeper](https://greenkeeper.io) Bot :palm_tree:

Start by inspecting the linked failing branch and the Travis CI build details, then reproduce the failure with grpc 1.22.2. Determine the cause of the build break and verify that the project builds successfully with the dependency update.

Written by the indexing model from the issue text.