periodically check reindex status

[AlternateIf]

aws opensearch failed me multiple times when reindexing big indices. apparently there is some time of connection time limit set and even passing "timeout" for the reinidex call did not help. When the time limit is reached an exception occurs. (i think it was a 504 gateway timeout)

so to fix this i switched to letting the reindex run asynchronously and only querying the status periodically. this way we get instant responses from the index call and don't run into timeouts.

We can refine this approach. this is just my WIP i used to temporarly fix for a project where that problem occured.

what do you think? @fashxp @mattamon

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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[AlternateIf]

https://medium.com/@dearyhud/whats-the-deal-with-hosted-aws-elasticsearch-service-timeouts-9f8885fa3050

this seems to also occur for opensearch on aws