Truncate log messages from the end

Our default pattern layout truncates log messages. This is to avoid
blowing disk space from excessively log messages, which can happen if a
message contains a mapping or an large query. Yet, we trunacte from the
beginning which is probably where the most germane information is. This
commit modifies the default pattern layout to trunacte from the end.

Relates #21609

distribution/src/main/resources/config/log4j2.properties

@@ -13,7 +13,7 @@ appender.rolling.type = RollingFile
 appender.rolling.name = rolling
 appender.rolling.fileName = ${sys:es.logs}.log
 appender.rolling.layout.type = PatternLayout
-appender.rolling.layout.pattern = [%d{ISO8601}][%-5p][%-25c{1.}] %marker%.10000m%n
+appender.rolling.layout.pattern = [%d{ISO8601}][%-5p][%-25c{1.}] %marker%.-10000m%n
 appender.rolling.filePattern = ${sys:es.logs}-%d{yyyy-MM-dd}.log
 appender.rolling.policies.type = Policies
 appender.rolling.policies.time.type = TimeBasedTriggeringPolicy
@@ -28,7 +28,7 @@ appender.deprecation_rolling.type = RollingFile
 appender.deprecation_rolling.name = deprecation_rolling
 appender.deprecation_rolling.fileName = ${sys:es.logs}_deprecation.log
 appender.deprecation_rolling.layout.type = PatternLayout
-appender.deprecation_rolling.layout.pattern = [%d{ISO8601}][%-5p][%-25c{1.}] %marker%.10000m%n
+appender.deprecation_rolling.layout.pattern = [%d{ISO8601}][%-5p][%-25c{1.}] %marker%.-10000m%n
 appender.deprecation_rolling.filePattern = ${sys:es.logs}_deprecation-%i.log.gz
 appender.deprecation_rolling.policies.type = Policies
 appender.deprecation_rolling.policies.size.type = SizeBasedTriggeringPolicy
@@ -45,7 +45,7 @@ appender.index_search_slowlog_rolling.type = RollingFile
 appender.index_search_slowlog_rolling.name = index_search_slowlog_rolling
 appender.index_search_slowlog_rolling.fileName = ${sys:es.logs}_index_search_slowlog.log
 appender.index_search_slowlog_rolling.layout.type = PatternLayout
-appender.index_search_slowlog_rolling.layout.pattern = [%d{ISO8601}][%-5p][%-25c] %marker%.10000m%n
+appender.index_search_slowlog_rolling.layout.pattern = [%d{ISO8601}][%-5p][%-25c] %marker%.-10000m%n
 appender.index_search_slowlog_rolling.filePattern = ${sys:es.logs}_index_search_slowlog-%d{yyyy-MM-dd}.log
 appender.index_search_slowlog_rolling.policies.type = Policies
 appender.index_search_slowlog_rolling.policies.time.type = TimeBasedTriggeringPolicy
@@ -61,7 +61,7 @@ appender.index_indexing_slowlog_rolling.type = RollingFile
 appender.index_indexing_slowlog_rolling.name = index_indexing_slowlog_rolling
 appender.index_indexing_slowlog_rolling.fileName = ${sys:es.logs}_index_indexing_slowlog.log
 appender.index_indexing_slowlog_rolling.layout.type = PatternLayout
-appender.index_indexing_slowlog_rolling.layout.pattern = [%d{ISO8601}][%-5p][%-25c] %marker%.10000m%n
+appender.index_indexing_slowlog_rolling.layout.pattern = [%d{ISO8601}][%-5p][%-25c] %marker%.-10000m%n
 appender.index_indexing_slowlog_rolling.filePattern = ${sys:es.logs}_index_indexing_slowlog-%d{yyyy-MM-dd}.log
 appender.index_indexing_slowlog_rolling.policies.type = Policies
 appender.index_indexing_slowlog_rolling.policies.time.type = TimeBasedTriggeringPolicy