feat: add test for missing @redocly/config type

[AlbinaBlazhko17]

What/Why/How?

We faced the issue when updating the version of openapi-core in other products. The problem was that we forgot to add new types in @redocly/config.

I created a unit test, which will fail if we forget to add types.

Reference

Discovered issue in PR #18391.

Testing

Manually.

Screenshots (optional)

Check yourself

• Code changed? - Tested with Redoc/Realm/Reunite (internal)
• All new/updated code is covered by tests
• New package installed? - Tested in different environments (browser/node)
• Documentation update considered

Security

• The security impact of the change has been considered
• Code follows company security practices and guidelines

[changeset-bot]

⚠️ No Changeset found

Latest commit: 5a79614

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[github-actions]

Command	Mean [s]	Min [s]	Max [s]	Relative
redocly lint packages/core/src/benchmark/benches/rebilly.yaml	1.408 ± 0.027	1.377	1.451	1.00
redocly-next lint packages/core/src/benchmark/benches/rebilly.yaml	1.410 ± 0.024	1.383	1.461	1.00 ± 0.03

[tatomyr]

I'm reluctant to add a unit test for this here. Imagine you just want to add a property--but you wouldn't be able to do it without releasing a new config version. Can you move it to something like a smoke test (so it's not required for merging PRs)?

[tatomyr]

Maybe term 'intergration test' is more relevant to our case though.