Removal of deprecated jmx configuration in solrconfig.xml of Solr cores dedup and audit

[saschaszott]

Description

This minor PR removes the deprecated jmx configuration in solrconfig.xml.

[saschaszott]

@jor4science, this is not production-critical.

[github-actions]

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[saschaszott]

@jor4science , do you have any updates on this issue?