Update dependency org.jboss.resteasy:resteasy-core to v6

Author: renovate[bot]

gradle/libs.versions.toml

@@ -14,7 +14,7 @@ opensaml = "2.6.4"
 org-json = "20250107"
 org-reflections = "0.9.11"
 poi = "5.4.1"
-resteasy = "4.7.10.Final"
+resteasy = "6.2.12.Final"
 slf4j = "1.7.36"
 solrj = "7.7.3"
 typesafeconfig = "0.1.0"