support biome-ignore-warn

[unional]

From the last conversation, the biome-ignore will ignore error/warn and will emit an unused warning when the underlying line has no error/warn.

But what if I want to make sure it is a warning?
The use case here is to write tests to configuration to proof it set certain rule as warn, instead of error or off

Yes this is a pretty niche use case, but want to throw it out there to see if there is some way or interest to handle that. 🍻