SharedState - handle race conditions

[b-ma]

const aCreated = await server.stateManager.create('a');
const aAttached = await client.stateManager.attach('a');

await aCreated.delete();
await aAttached.detach(); // program is stuck here...

• DELETE_REQUEST is received first on the SharedStatePrivate which deletes all its listeners
• DETACH_REQUEST is sent but have not response, then it never resolves so the program is stuck...

Possible fix:

Keep track of all requests and reject them if a DELETE_NOTIFICATION or a DETACH_NOTIFICATION is received