[BUG] Revisit AlertingException wrap logic

[eirsep]

this is the actual error that needs to be surfaced

[2023-03-03T23:08:57,030][ERROR][o.o.a.u.AlertingException] [d52c8d13a5350334e8ebfd39b5805d5b] Alerting error: RemoteTransportException[[784e3b9e8589583cc18deb09efece92a][10.212.49.29:9300][indices:admin/mapping/put]]; nested: IllegalArgumentException[Limit of total fields [1000] has been exceeded];

But the error being seen is

{
    "error": {
        "caused_by": {
            "reason": "org.opensearch.transport.RemoteTransportException: [784e3b9e8589583cc18deb09efece92a][10.212.49.29:9300][indices:admin/mapping/put]",
            "type": "exception"
        },
        "reason": "[784e3b9e8589583cc18deb09efece92a][10.212.49.29:9300][indices:admin/mapping/put]",
        "root_cause": [
            {
                "reason": "[784e3b9e8589583cc18deb09efece92a][10.212.49.29:9300][indices:admin/mapping/put]",
                "type": "alerting_exception"
            }
        ],
        "type": "alerting_exception"
    },
    "status": 500
}

which really doesnt give the relevant stacktrack required to understand what went wrong

[petardz]

This is why we do "unwrapping" of exception when checking for specific errors. Maybe we should do the same in this wrap function?