Merge pull request #11383 from nextcloud/dependabot/gradle/com.diffplug.spotless-6.15.0

Build(deps): Bump com.diffplug.spotless from 6.14.1 to 6.15.0

app/build.gradle

@@ -17,7 +17,7 @@ buildscript {
 }
 
 plugins {
-    id "com.diffplug.spotless" version "6.14.1"
+    id "com.diffplug.spotless" version "6.15.0"
 }
 
 apply plugin: 'com.android.application'