docs: correct number of commands for scaffolding an app

[tom-draper]

Closes [none]

✅ Checklist

• I have followed every step in the contributing guide (updated 2022-10-06).
• The PR title follows the convention we established conventional-commit
• I performed a functional test on my final commit

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Changelog

Corrected a minor typo in README.md for the number of different commands for scaffolding an app.

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