Fix typos in README.md

[CarlosCalgaro]

Motivation / Background

This Pull Request has been created because I noticed a few typos in the README.md file.

Additional information

Checklist

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• This Pull Request is related to one change. Changes that are unrelated should be opened in separate PRs.
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[CarlosCalgaro]

Hi! I opened this PR to fix a few small typos I noticed while reading the docs.
Please let me know if this change is useful for the project. If not, I’m happy to close it. Thanks!

[stefannibrasil]

Thank you!