event_mgmt : make registration and provider service more resilient for 409 conflict errors #199

Expected Behaviour

Conflict errors should be handled gracefully while a registration or provider is being created. In case of conflict the conflicting registration id or providerId should be fetched from the exception response header and used to update that registration or provider

See jira issue https://jira.corp.adobe.com/browse/CI-6365

Actual Behaviour

Conflict Exception is thrown and api terminates without further processing

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