feat: explicit support of bearer security scheme

[Nautigsam]

• Add a type for bearer security scheme.
• Add a test to verify we fail when using a scheme not supported by Swagger2.0.

Fix #1183

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[github-actions]

Hello there Nautigsam 👋

Thank you and congrats 🎉 for opening your first PR on this project.✨

We will review the following PR soon! 👀

[WoH]

LGTM, thanks!