LPS-52173 Enable periodic autoSoftCommit by default

For performance reasons (LPS-47182) we don't force anymore a hard commit
on every update. This commit showcases how to configure Near Real Time
Searching
(https://cwiki.apache.org/confluence/display/solr/Near+Real+Time+Searching)
to achieve a similar effect.

https://issues.liferay.com/browse/LPS-52173