gpt-oss-20b and gpt-oss-120b playgroud not having a model

### Example URL(s)

https://playground.ai.cloudflare.com/?model=%40cf%2Fopenai%2Fgpt-oss-20b doesn't have a model to select

### Actual Behavior

No model is selected, and get a 400 error code

### Expected Behavior

Select a model and a 200 error code

### Additional information

_No response_