fix: move to ubuntu 18.04

[aslafy-z]

19.10 is not supported by https://github.com/actions/setup-python action. Move to a LTS version.
See

• self-hosted runner failing while trying to get version actions/setup-python#96 (comment)
• https://raw.githubusercontent.com/actions/python-versions/master/versions-manifest.json

[myoung34]

Unless I'm misunderstanding something, Bionic is already supported and deployed:

Base dockerfile -> artifact

Final dockerfile (not pinned to a GH action tag) -> artifact

Final dockerfile (pinned to a GH action tag) -> artifact

to use this you just wouldnt pin your runner to latest (which is eoan) but to ubuntu-bionic (essentially latest but on bionic and not eoan):

docker run -d --restart always --name github-runner \
  -e RUNNER_NAME_PREFIX="myrunner" \
  -e ACCESS_TOKEN="footoken" \
  -e RUNNER_WORKDIR="/tmp/github-runner-your-repo" \
  -e ORG_RUNNER="true" \
  -e ORG_NAME="octokode" \
  -e LABELS="my-label,other-label" \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -v /tmp/github-runner-your-repo:/tmp/github-runner-your-repo \
  myoung34/github-runner:ubuntu-bionic

or a specific tag for bionic:

docker run -d --restart always --name github-runner \
  -e RUNNER_NAME_PREFIX="myrunner" \
  -e ACCESS_TOKEN="footoken" \
  -e RUNNER_WORKDIR="/tmp/github-runner-your-repo" \
  -e ORG_RUNNER="true" \
  -e ORG_NAME="octokode" \
  -e LABELS="my-label,other-label" \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -v /tmp/github-runner-your-repo:/tmp/github-runner-your-repo \
  myoung34/github-runner:2.267.0-ubuntu-bionic

[aslafy-z]

Oh great! I missed that, sorry. It might be good to add a mention in the README about these tags. Thanks for your work!

[myoung34]

Ill add a TODO and add that to the README, you're right that its easy to miss.