Remove no longer needed safe-guard around formatting.

Author: SimY4

gradle/check-checkstyle.gradle

@@ -2,7 +2,7 @@ apply plugin: 'com.diffplug.spotless'
 
 spotless {
     java {
-        if (!JavaVersion.current().isCompatibleWith(JavaVersion.VERSION_16)) { googleJavaFormat() }
+        googleJavaFormat()
         trimTrailingWhitespace()
         removeUnusedImports()
         licenseHeaderFile rootProject.file('gradle/license.header')