[9.0] (backport #18018) [DOCS] Fix nullable type linting error in OpenAPI document

[mergify]

Release notes

[rn:skip]

What does this PR do?

This PR addresses the following linting errors reported

[1] redocly.yaml:29:3 at #/rules/path-excludes-patterns

Property `path-excludes-patterns` is not expected here.

27 | no-ambiguous-paths: warn
28 | no-identical-paths: error
29 | path-excludes-patterns:
30 |   severity: error
31 |   patterns:

Warning was generated by the configuration struct rule.

[2] redocly.yaml:37:3 at #/rules/spec

Property `spec` is not expected here.

35 |  operation-2xx-response: off
36 | # Schema
37 |  spec: off
38 |  spec-strict-refs: off
39 | # Tags

Warning was generated by the configuration struct rule.

...

[2] logstash-api.yaml:2267:15 at #/components/schemas/PipelineReloadStats/properties/reloads/properties/last_error/nullable

Property `nullable` is not expected here.

2265 | last_error:
2266 |   type: string
2267 |   nullable: true
2268 | successes:
2269 |   type: integer

Error was generated by the struct rule.

Why is it important/What is the impact to the user?

The redocly linter's behaviour changed per https://redocly.com/docs/cli/guides/migrate-to-v2 thus the configuration needed to be updated.

nullable: true is the format for OpenAPI 3.0 and that also changed in 3.1 so updates were required in that formatting too.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files (and/or docker env variables)
• I have added tests that prove my fix is effective or that my feature works

Author's Checklist

N/A

How to test this PR locally

redocly lint logstash-api.yaml --config redocly.yaml

Related issues

N/A

Use cases

N/A

Screenshots

N/A

Logs

N/A

---

This is an automatic backport of pull request #18018 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 34a7c67 has failed:

On branch mergify/bp/9.0/pr-18018
Your branch is up to date with 'origin/9.0'.

You are currently cherry-picking commit 34a7c676.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   docs/static/spec/openapi/redocly.yaml

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   docs/static/spec/openapi/logstash-api.yaml

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[lcawl]

There were no occurrences of nullable: true in the OpenAPI document in this branch, so only the linting configuration file updates are required.

[mergify]

This pull request has not been merged yet. Could you please review and merge it @lcawl? 🙏

[mergify]

This pull request has not been merged yet. Could you please review and merge it @lcawl? 🙏