Update to support Solr 8.x

As a developer I can use SOLR v8 in my projects and know that I am doing it in a supported way, so that I am on the latest version with no known CVE/Secuirty concerns.

Recommendations:

At least verify that SOLR 8 is compabilible.

At least document the necessary and approved configuration to use SOLR 8

Evaluate if it would cause problems to change our default version of SOLR to v8.

Determine when this update should be made (6.2 or 6.3)

If appropriate, do the upgrade.

Notes

Update to SOLR module to use Solr 8.x as there are various reported CVE on Solr 7.

https://solr.apache.org/security.html