DOCSP-12530: [KAFKA] Add offset.partition.name configuration option (#57)

* DOCSP-12530: [KAFKA] Add offset.partition.name configuration option

Author: steveren

source/kafka-source.txt

@@ -269,6 +269,16 @@ an example source connector configuration file, see
        | **Default:** ""
        | **Accepted Values**: A valid Kafka topic name
 
+   * - offset.partition.name
+     - string
+     - | A custom offset partition name to use. This option can be used to
+         start a new change stream when an existing offset contains an
+         invalid resume token. If blank, the default partition name based
+         on the connection details is used.
+       |
+       | **Default:** ""
+       | **Accepted Values**: A valid partition name
+
 .. note::
 
    The default maximum size for Kafka messages is 1MB. Update the