Update dependency com.diffplug.spotless to v8.9.0

Author: renovate[bot]

gradle/libs.versions.toml

@@ -14,7 +14,7 @@ protobuf = "4.34.2"
 protobuf-plugin = "0.10.0"
 scip-bindings = "0.9.0"
 shadow = "9.6.1"
-spotless = "8.8.0"
+spotless = "8.9.0"
 vanniktech-maven-publish = "0.37.0"
 
 [libraries]