teleport configuration location not set in docker

[stevenGravy]

Description

What happened:

The 6.0.0-rc.1 docker container does not set the env variable TELEPORT_CONFIG_FILE to the /etc/teleport/teleport.yaml path so tctl throws an error .

$ docker exec -it teleport bash                 
root@localhost:/# tctl users ls
ERROR:
        file /etc/teleport.yaml is not found

What you expected to happen:
tctl on the auth service would work as previously it did in a docker container without specifying the config location.

Reproduction Steps

As minimally and precisely as possible, describe step-by-step how to reproduce the problem.

1. Follow the https://goteleport.com/teleport/docs/quickstart-docker/ quickstart to setup a docker-compose
   2.test tctl usage on 5.1.2 such as tctl users ls in an exec session of teleport
   3.try the same in 6.0.0-rc.1

Server Details

• Teleport version (run teleport version): 6.0.0-rc.1
• Server OS (e.g. from /etc/os-release): docker, ubuntu
• Where are you running Teleport? (e.g. AWS, GCP, Dedicated Hardware): workstation
• Additional details:

Which platform(s)

• Teleport Open Source
• Teleport Cloud
• Teleport Enterprise
• Other

Which component(s)

• [] Server Access
• Kubernetes Access
• Application Access
• Database Access
• CLI Clients
• Web Clients
• Other