Modify logger config to link deprecation logger to root logger by default (#18326) (#18379)

(cherry picked from commit 915b69f)

Co-authored-by: Álex Cámara Lara <[email protected]>

Author: mergify[bot]

config/log4j2.properties

@@ -157,9 +157,9 @@ appender.deprecation_rolling.strategy.max = 30
 logger.deprecation.name = org.logstash.deprecation
 logger.deprecation.level = WARN
 logger.deprecation.appenderRef.deprecation_rolling.ref = deprecation_plain_rolling
-logger.deprecation.additivity = false
+logger.deprecation.additivity = true
 
 logger.deprecation_root.name = deprecation
 logger.deprecation_root.level = WARN
 logger.deprecation_root.appenderRef.deprecation_rolling.ref = deprecation_plain_rolling
-logger.deprecation_root.additivity = false
+logger.deprecation_root.additivity = true

logstash-core/lib/logstash/runner.rb

@@ -282,7 +282,7 @@ def execute
                                            :java_home => java.lang.System.getProperty("java.home"))
     end
 
-    logger.warn I18n.t("logstash.runner.java.home") if ENV["JAVA_HOME"]
+    deprecation_logger.deprecated I18n.t("logstash.runner.java.home") if ENV["JAVA_HOME"]
     # Skip any validation and just return the version
     if version?
       show_version