fix indent in script configure_feature_flags.rb

Author: kkimurak

assets/runtime/scripts/configure_feature_flags.rb

@@ -21,7 +21,7 @@ def available_feature_flags()
       feature_flag_yamls.concat(Dir.glob("#{Gitlab.root}/ee/config/feature_flags/**/*.yml"))
     end if
 
-      list = feature_flag_yamls.map { |p| File.basename(p, File.extname(p)) }
+    list = feature_flag_yamls.map { |p| File.basename(p, File.extname(p)) }
     list
   end