Update dependency com.diffplug.spotless to v8.4.0

Author: solrbot

gradle/libs.versions.toml

@@ -76,7 +76,7 @@ cutterslade-analyze = "1.10.0"
 cuvs-java = "25.10.0"
 cuvs-lucene = "25.10.0"
 decompose = "3.4.0"
-diffplug-spotless = "8.3.0"
+diffplug-spotless = "8.4.0"
 # @keep Use for dockerfile JRE version
 dockerfile-baseimage-java = "25"
 dropwizard-metrics = "4.2.33"