The following settings are now no-ops:
* xpack.flattened.enabled
* xpack.logstash.enabled
* xpack.rollup.enabled
* xpack.slm.enabled
* xpack.sql.enabled
* xpack.transform.enabled
* xpack.vectors.enabled
Since these settings no longer need to be checked, we can remove settings
parameters from a number of constructors and methods, and do so in this
commit.
We also update documentation to remove references to these settings.
* Add test for SQL not being available error message in JDBC.
* Add a new qa sub-project that explicitly disables SQL XPack module in Gradle.
(cherry picked from commit 8a1ac8a3a88a325ec9b99963e0fa288c18ee0ee5)