Upgrade solr to latest LTS series

[adborden]

User Story

As an operator, I want to use LTS solr so that my solr cluster has a long runway for support and security updates.

Details

Before getting too far into this, we should check that CKAN indeed supports 7.7.x. I've seem some anecdotal evidence that the most compatible version is 6.6.x.

Acceptance Criteria

• datagov-deploy-solr supports 7.7
• datagov-deploy is updated to solr 7.7

[jbrown-xentity]

Current version is 8.6.3

[adborden]

Yes, 8.x is current but we want an LTS release, not the latest.

At the moment, it looks like CKAN 2.9 is not compatible with Solr 8 although the support implementation has started.

[mogul]

We're still limited by CKAN only supporting through Solr 6.6.6 upstream.

[nickumia-reisys]

We have successfully updated catalog to use the latest LTS release of Solr.

There is an issue to finish updating inventory to use Solr 8 as well. This issue has been superseded by #3697 for Inventory.

[hkdctol]

Closing this as we've updated Solr.