`{}` meaning no body not respected when using `@bodyRoot`

When using `@bodyRoot` it shouldnt' change the interpretation just means we should start resolving the body from that property, but seems like we are not reading it as void.

[Playground Link](https://typespec.io/playground?c=aW1wb3J0ICJAdHlwZXNwZWMvaHR0cCI7Cgp1c2luZyBUeXBlU3BlYy5IdHRwOwpAc2VydmljZSh7CiAgdGl0bGU6ICJXaWRnZXQgU8YbIiwKfSkKbmFtZXNwYWNlIERlbW%2FHGzsKCkByb3V0ZSgiMSIpIG9wIHQxKCk6IHt9O8kZMscZMsUZQGJvZHlSb290IF%2FEJ307&e=%40typespec%2Fopenapi3&options=%7B%22linterRuleSet%22%3A%7B%22extends%22%3A%5B%22%40typespec%2Fhttp%2Fall%22%5D%7D%7D)