Upgrade to Solr 9.4.0

Solr has been upgraded to release 9.4.0. This release fixes several bugs and security issues and offers new features. See https://solr.apache.org/docs/9_4_0/changes/Changes.html for a list of changes. Alongside, a new coremedia/solr-base Docker image with tag 2.1-cm-9.4.0 was released.

Follow Section, “Upgrade to Solr 9.4.0” for upgrade information.

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