Frequent timeout errors

I am using this library in a concurrent environment but I frequently get timeout errors when there shouldn't be any.

I am instantiating the `Elasticsearch` object with `maxsize=200` since it could be called by around 200 coroutines at any given time. The default value for the timeout is 10 seconds and should be plenty, but I increased it to 30 seconds and even if the timeouts diminish in frequency I still get a lot of them.