Update plugin spotless to v8.1.0

Author: renovate[bot]

gradle/libs.versions.toml

@@ -10,6 +10,6 @@ coroutines = "org.jetbrains.kotlinx:kotlinx-coroutines-core:1.10.2"
 
 [plugins]
 kotlinJvm = { id = "org.jetbrains.kotlin.jvm", version = "2.2.21" }
-spotless = { id = "com.diffplug.spotless", version = "8.0.0" }
+spotless = { id = "com.diffplug.spotless", version = "8.1.0" }
 publish = { id = "com.vanniktech.maven.publish", version = "0.35.0" }
 dokka = { id = "org.jetbrains.dokka", version = "2.1.0" }