Remove extra line from readme example

[sanders41]

Pull Request

I just noticed that when I was updating the readme with a seriaizer example I accidentally include a line from a test that doesn't make sense in the context of the example. This removes that line.

Related issue

Fixes #

What does this PR do?

• ...

PR checklist

Please check if your PR fulfills the following requirements:

• [ ] Does this PR fix an existing issue, or have you listed the changes applied in the PR description (and why they are needed)?
• [ ] Have you read the contributing guidelines?
• [ ] Have you made sure that the title is accurate and descriptive of the changes?

Thank you so much for contributing to Meilisearch!

[meili-bors[bot]]

Build failed:

• integration-tests (3.10)

[curquiza]

bors merge

[meili-bors[bot]]

Build succeeded:

• integration-tests (3.10)
• integration-tests (3.11)
• integration-tests (3.12)
• integration-tests (3.8)
• integration-tests (3.9)
• mypy
• pylint