In hybrid SDKs such as React Native, we want to be able to close the SDK in JS and have that close call flow through to all inner SDKs.

For that we need make sure close is implemented in all layers and works as intended.
The spec defined a close method on the client but we're looking for a close on the static API, which will be added to the spec.

The expected behavior is that if a crash happens after close is called, an envelope with the crash data isn't generated.