fix(docker-compose): fix yml to use mapping instead of list

[juliangieseke]

further reading:
docker/compose#2854
https://docs.docker.com/compose/compose-file/#args

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this PR unblocks #2547 - rebase it on this one and it should run successfully when run through docker-compose exec toolchain dcos-system-test-driver /dcos-ui/system-tests/driver-config/jenkins.sh we decided to merge #2547 before this one because the tests are running on ci, only our local docker-compose setup is broken.

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HINT: you can prevent the cluster (and tests) from being started with adding exit 1 in the first line of system-tests/_scripts/launch-cluster.sh - it will fail with Process '../_scripts/launch-cluster.sh' exited with 1 which is okay and means the config is correctly parsed.

if you see the error @nLight mentioned in #2547 it didnt work.

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Caveat: it looks like docker doesnt recognize when you change the passed variables after docker-compose up -d 🤔 had to export the changed var…

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[juliangieseke]

Alfred test this please

[juliangieseke]

Alfred test this please

[ahoskins]

@juliangieseke I'm a bit confused: in the description it says this PR unblocks #2547, but 2547 has merged without this merging first. Is this PR still needed?

[juliangieseke]

Yes, we decided that this one isnt blocking #2547, because it only prevents us from running the tests through docker-compose - but it is still a fix we should apply.

I simply forgot to update this PR after merging the other one

[ahoskins]

Makes sense, thanks for the clarification @juliangieseke