An in-range update of broccoli-concat is breaking the build 🚨

## The dependency [broccoli-concat](https://github.com/ember-cli/broccoli-concat) was updated from `3.7.1` to `3.7.2`.

🚨 [View failing branch](https://github.com/ember-fastboot/ember-cli-fastboot/compare/master...ember-fastboot:greenkeeper%2Fbroccoli-concat-3.7.2).

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

broccoli-concat 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 is in progress ([Details](https://travis-ci.org/ember-fastboot/ember-cli-fastboot/builds/437381002?utm_source=github_status&utm_medium=notification)).
- ❌ **continuous-integration/appveyor/branch:** AppVeyor build failed ([Details](https://ci.appveyor.com/project/embercli/ember-cli-fastboot/build/570)).

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Commits

The new version differs by 3 commits.

• fe0b7ce release v3.7.2 🎉


• d9e720e Merge pull request #133 from akashdsouza/patch_retain_mitigate_memory_overhead


• b39a15a [PATCH]Read synchronously for larger files while concatenating

See the full diff

FAQ and help

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