If .._CACHE_INDEX is enabled the default should be to set auto-config=true

If a cache should have an index the environment variable <cache name>_CACHE_INDEXED can be set to ALL/LOCAL.
This implies the knowledge how indexing is working.
To simplify the configuration the configuration default should be "AUTO" and also used if something wrong is added.

As a result the XML need to be
<indexing auto-config="true"/>