Allow resetting global providers

[lmolkova]

Some frameworks do some questionable things, like setting global OTel provider to export telemetry to their own destination e.g. https://github.com/Chainlit/chainlit/blob/6ec007032945dfd6a1a608cc3c8074bd2f643d0c/backend/chainlit/telemetry.py#L65

It must be possible to override their configuration. Currently once global tracer/metrics/logs provider is set, there is no way to override it.

Related: https://github.com/Chainlit/chainlit/issues/2127

[lzchen]

@lmolkova

I'm assuming you are asking for functionality to ALLOW overriding of the global trace provider (like an option), not change the way the api works right?