Use longer Elastic timeout for write operation

With the default rest-client, we can configure connection.timeout.ms and socket.timeout.ms.
Controlling the socket timeout is a way to limit queries that take too long and impact the UI rendering, 20s is a good default.
But this could lead to stream failure when submitting an indexing command.
Note also that bulk indexing commands use a custom timeout which is 60s by default,
we want a longer timeout for write operations.