Migrate to Non-Bitnami Indexer Chart

Metacat itself no longer has any direct Bitnami dependencies (now uses CNPG instead of bitnami ppostgres). However, metacat depends on the `dataone-indexer` subchart, which has bitnami dependencies for rabbitmwq, solr and zookeeper. Migrating these away from bitnami will require some Metacat helm chart changes, thus the need for this Issue to anchor the relevant PRs.