Auto-generated OpenAPI is *incorrect* for /aws/creds

[maxb]

Describe the bug

The auto-generated OpenAPI (from /sys/internal/specs/openapi) generates incorrect documentation for the AWS secrets engine API.

To Reproduce

1. Mount an instance of the AWS secrets engine
2. Visit the built-in Vault Swagger UI (at /ui/vault/api-explorer)
3. Find the endpoint /aws/creds
4. Compare with the actual API docs for the AWS secrets engine
5. Realise that actually there is no such API endpoint /aws/creds, only /aws/creds/{name}

Expected behavior

Auto-generated OpenAPI should accurately reflect the actual APIs in Vault.

Additional context

It would seem highly likely that the bug is that the Vault OpenAPI generator doesn't correctly understand what to do with regexs employing alternatives:

		Pattern: "(creds|sts)/" + framework.GenericNameWithAtRegex("name"),

vault/builtin/logical/aws/path_user.go

Line 20 in 818502b

Pattern: "(creds|sts)/" + framework.GenericNameWithAtRegex("name"),

[averche]

Resolved in #13487