Make and configure a custom Valkyrie Indexing Adapter

[laritakr]

Descriptive summary

The Hyrax indexing adapter does not correctly find the URL to use for Hyku tenants in all situations. Changes were made overriding Hyrax's behavior. This ticket is to instead consider making and configuring a new indexing adapter in Hyku.

Rationale

Setting up and configuring custom adapters is the norm for Valkyrization. Prior work to fix the solr url issues overrides the indexing adapter, which doesn't make sense given the adapter paradigm.

Related work

Issues:
scientist-softserv/hykuup_knapsack#194
#2177

Code changes to address the issues:
Stab in the dark attempt to fix
#2179
#2180
#2182