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### Motivation / Background

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### Detail


### Alternative approaches considered (if applicable)

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### Checklist

The resources of our team are limited. **There are a couple of things that you can do to help us merge your PR faster**:

- [ ] I wrote tests for the changes.
- [ ] All tests are passing.
  - If you are testing a Pub/Sub, you can start Docker with `make up`.
  - You can start with `make test_short` for a quick check.
  - If you want to run all tests, use `make test`.
- [ ] Code has no breaking changes.
- [ ] _(If applicable)_ documentation on [watermill.io](https://watermill.io/) is updated.
  - Documentation is built in the [github.com/ThreeDotsLabs/watermill/docs](https://github.com/ThreeDotsLabs/watermill/tree/master/docs).
  - You can find development instructions in the [DEVELOP.md](https://github.com/ThreeDotsLabs/watermill/tree/master/docs/DEVELOP.md).