[Aptos Data Client] Update the poller to better handle in-flight requests.
[Aptos Data Client] Update the poller to better handle in-flight
requests.

Closes: #1059

aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core