Update dependency com.diffplug.spotless to v8

Author: renovate[bot]

gradle/libs.versions.toml

@@ -8,7 +8,7 @@ licenser = "0.6.1"
 mockito-kotlin = "6.0.0"
 nexus-publish-plugin = "2.0.0"
 placeholderapi = "2.11.6"
-spotless = "7.2.1"
+spotless = "8.0.0"
 vault-api = "1.7.1"
 
 [libraries]