Update plugin com-diffplug-spotless to v8.6.0 (#489)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

gradle/libs.versions.toml

@@ -1,6 +1,6 @@
 [plugins]
 
-com-diffplug-spotless = { id = "com.diffplug.spotless", version = "8.5.1" }
+com-diffplug-spotless = { id = "com.diffplug.spotless", version = "8.6.0" }
 
 com-gradleup-shadow = { id = "com.gradleup.shadow", version = "9.4.2" }