Brief summary of the bug. What is it ? Where is it ?

As explained in SUPPORT-13747 in case of a connection error to the C7 engine-rest API, the original exception is swallowed and converter to a generic OptimizeRuntimeException that hides the original issue and makes it hard to debug such cases.

Steps to reproduce:

1. Misconfigure the C7 engine connection (so that the connection fails, e.g. wrong host)
2. Start Optimize

Actual result:

3. Observe a generic error "Engine didn't respond. Can not verify this engine's version" being logged, without any information on the cause/underlying issue.

Expected result:

4. The causing exception should get logged as well to give insights on what the underlying issue is