dependabot: bump com.diffplug.spotless from 6.21.0 to 6.22.0 (#510)

Bumps com.diffplug.spotless from 6.21.0 to 6.22.0.

---
updated-dependencies:
- dependency-name: com.diffplug.spotless
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

build.gradle

@@ -26,7 +26,7 @@ buildscript {
 plugins {
     id 'com.netflix.nebula.ospackage' version "11.5.0"
     id 'java-library'
-    id "com.diffplug.spotless" version "6.21.0" apply false
+    id "com.diffplug.spotless" version "6.22.0" apply false
 }
 
 apply plugin: 'opensearch.opensearchplugin'