fix: treat nullable property as optional

[janne-slamcore]

Description

Add a test for a required, but nullable, union type and update the Pydantic preset to treat nullable properties as optional.

Related Issue

Fixes #2000

Checklist

• The code follows the project's coding standards and is properly linted (npm run lint).
• Tests have been added or updated to cover the changes.
• Documentation has been updated to reflect the changes.
• All tests pass successfully locally.(npm run test).

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[netlify]

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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[coveralls]

Pull Request Test Coverage Report for Build 9111354819

Details

• 3 of 3 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.003%) to 92.303%

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Totals
Change from base Build 9108384335:	0.003%
Covered Lines:	5996
Relevant Lines:	6327

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💛 - Coveralls

[jonaslagoni]

Thanks @janne-slamcore 🤙

[jonaslagoni]

@all-contributors please add @janne-slamcore for code, test

[allcontributors]

@jonaslagoni

I've put up a pull request to add @janne-slamcore! 🎉

[asyncapi-bot]

🎉 This PR is included in version 3.5.1 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀