Docker Song and Score client setup with docker exec commands

[MitchellShiell]

Updated environment variables to appropriately match those outlined in following files:

• https://github.com/overture-stack/SONG/blob/develop/song-client/src/main/resources/application.yml
• https://github.com/overture-stack/SCORE/blob/develop/score-client/src/main/resources/application.yml

Updated all commands with the following formatting docker exec {container/client} sh -c "{command}"

Question for Dev Team - Why is our score-client container called score? Can we update this to score-client?

[ciaranschutte]

looks good to me and the "access token" comment and "score vs score-client" comment can be addressed in future as discussed on slack. approving,