Unify Kibana & Elasticsearch logging config keys

[mshustov]

The config keys naming in Kibana logging config follows the log4j2 conventions https://logging.apache.org/log4j/2.x/manual/configuration.html
While the logging config in elasticsearch follows a bit different convention. https://www.elastic.co/guide/en/elasticsearch/reference/current/logging.html
https://github.com/elastic/elasticsearch/blob/a4a79670f85d5c135c1ad668c387808fffd733f7/qa/logging-config/src/test/resources/org/elasticsearch/common/logging/json_layout/log4j2.properties
Some examples, not full:

Kibana logging config	Elasticsearch logging config
logging.appenders.xxx	appender.xxx
logging.loggers.xxx	logger.xxx
logging.root.xxx	rootLogger.xxx
logging.appenders.xxx.kind	appender.xxx.type

We can narrow the naming difference as much as possible to reduce the cognitive load on the consumer. We still can have logging-prefix to follow the platform principles, even though the platform is allowed to have exceptions to the rule.

Kibana logging config	Kibana config follows ES conventions
logging.appenders.xxx	logging.appender.xxx
logging.loggers.xxx	logging.logger.xxx
logging.root.xxx	logging.root.xxx
logging.appenders.xxx.kind	logging.appender.xxx.type

[elasticmachine]

Pinging @elastic/kibana-platform (Team:Platform)

[pgayvallet]

The Kibana config follows ES conventions you are suggesting looks fine to me.

We still can have logging-prefix to follow the platform principles, even though the platform is allowed to have exceptions to the rule.

I think keeping the prefix really makes sense.

[joshdover]

I like the proposed Kibana settings, but I also think we should have Elasticsearch align with us here as much as possible. Personally, it seems like the appender.xxx config key in ES is very unclear. Adding the logging prefix would make sense to me.

[elasticmachine]

Pinging @elastic/kibana-operations (Team:Operations)