Update source.md, finx typos

[NicholasWilsonDEV]

Please read How to contribute before creating a submission.

Description and links to repo and pubdev if any

I really enjoyed using this project, nice work! Caught a couple of typos in the README though 😛

Submission description/links here

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Checklist

• [x] I read How to contribute
• [x] I edited the SOURCE.md file only
• [ ] Added a link to the repo in the PR

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