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Describe the bug

Routes that accept both form and json bodies through multiple controller actions with [ConsumesAttribute], a documented, supported use case of aspnetcore, are not emitted correctly by Microsoft.AspNetCore.OpenApi.

The comment on these lines is incorrect:

Expected Behavior

Both JSON and form content types are listed for the endpoint in requestBody.content in the OpenAPI document.

Steps To Reproduce

Write the exact example from the [Consumes] documentation at https://learn.microsoft.com/en-us/aspnet/core/web-api/?view=aspnetcore-9.0#define-supported-request-content-types-with-the-consumes-attribute-1:

[ApiController]
[Route("api/[controller]")]
public class ConsumesController : ControllerBase
{
    [HttpPost]
    [Consumes("application/json")]
    public IActionResult PostJson(IEnumerable<int> values) =>
        Ok(new { Consumes = "application/json", Values = values });

    [HttpPost]
    [Consumes("application/x-www-form-urlencoded")]
    public IActionResult PostForm([FromForm] IEnumerable<int> values) =>
        Ok(new { Consumes = "application/x-www-form-urlencoded", Values = values });
}

Observe that the JSON body is excluded from the OpenAPI document produced by Microsoft.AspNetCore.OpenApi. Only the form data body is present:

    "/api/Consumes": {
      "post": {
        "tags": [
          "Consumes"
        ],
        "requestBody": {
          "content": {
            "application/x-www-form-urlencoded": {
              "schema": {
                "type": "object",
                "properties": {
                  "values": {
                    "type": "array",
                    "items": {
                      "type": "integer",
                      "format": "int32"
                    }
                  }
                }
              }
            }
          },
          "required": true
        },
        "responses": {
          "200": {
            "description": "OK"
          }
        }
      }
    },

Exceptions (if any)

No response

.NET Version

9.0.100-rc.2.24474.11

Anything else?

No response