[META 773] Service environment correlation

[elastic-apm-tech]

See meta issue for the description and details:

• Meta issue: Service environment correlation apm#773

[trentm]

This is implemented in the ecs-logging-nodejs packages now: @elastic/ecs-morgan-format@1.4.0, @elastic/ecs-pino-format@1.4.0, @elastic/ecs-winston-format@1.4.0