- `respond_to any` doesn't allow to specify a content type and
  the content type in the response will be based on the request
  format.

  ```ruby
    def my_action
      respond_to do |format|
        format.html { render(html: 'hello') }
        format.any { render(json: { foo: 'bar'}) }
      end
    end

    get('my_action.csv')
    # Before this patch, content type was `text/csv'
    # Ather this patch, content type is correctly set to whateve we did in the `format.any` block
  ```

  If the client specify the type of data he wants but the server
  doesn't know how to handle it and return plain text (or whatever)
  I don't think it make sense to falsey claim that we are returning
  a `text/csv` a response where in fact we are returning something else.

  Fix #37345