LOG : add tpsvc log environment variable to the docker image

The TPSVC base docker image used by the service is using filebeat to send logs to kafka
there are some environment variable to be configured like :
KAFKA_HOSTS
LOG_PATH

where the kafka host is the url to connect to kafka so it requires to be set externally.
but the LOG_PATH is required to tell filebeat where to find logs and it should not be set externally but set in the docker built docker image.
This jira is to set LOG_PATH properly.