JVM extended pause can delay kill switch activation

If the JVM pauses for an extended period of time (for example, due to a hypervisor moving a VM to a different host) the health check kill switch might not active in time to prevent the connector from writing an obsolete version of a document to Elasticsearch. Obsolete because the leader may have reassigned the vbucket to another worker, and that worker may have written multiple versions of the document to Couchbase during the time the zombie worker is paused. When the zombie worker wakes up, it may overwrite the current version of the document with the old version it was processing at the time it was paused.

Detect when this occurs and report it to the user somehow.