Retry subscribe to Salesforce event when server returns 503 Server too busy

[mohitj13]

EMP Connector fails retry subscription when SF result in Server too busy response. Instead of dumping need to capture the response and retry again for subscription

Logs that the server returns additional information:

{ext={sfdc={failureReason=503::Server is too busy. Please try your request again later.}}, ...}

As described in the Salesforce documentation here: https://developer.salesforce.com/docs/atlas.en-us.api_streaming.meta/api_streaming/streaming_handling_errors.htm

the 503 Server too busy is a documented error that should/can be retried.

It would greatly add to the resilience of our system if the Salesforce component would automatically retry a subscribe if failed due to a temporary error.