RestForwarder: Avoid retrying non recoverable exceptions

According to the documentation [1], there are other exceptions that are
considered non recoverable and that should not be retried. This includes
the cases when, for example, the URL is absent or malformed or any other
error in the HTTP protocol.

[1] https://hc.apache.org/httpcomponents-client-ga/tutorial/html/fundamentals.html#d5e279

Change-Id: Ic9141606e87f283d9308081443e9f52eef35284c
1 file changed