[mod] 3.8: Use 3.8-slim-buster image as v3.8 is out

1 job for master in 59 seconds (queued for 1 minute and 28 seconds)
Status Name Job ID Coverage
  Test
failed test_build_image #30374
docker

00:00:59

 
Name Stage Failure
failed
test_build_image Test There has been a runner system failure, please try again
 ---> 6b52e13b1d32
Step 2/3 : RUN apt update && apt install --yes libsodium23 libffi-dev gcc black make && rm -rf /var/lib/apt/lists
---> Using cache
---> 4b329a2a53a3
Step 3/3 : RUN pip3 install poetry --pre
---> Using cache
---> 6f718170e2e9
Successfully built 6f718170e2e9
ERROR: Job failed (system failure): Error response from daemon: Cannot link to a non running container: /runner-YX9a3LzN-project-272-concurrent-0-docker-0 AS /runner-YX9a3LzN-project-272-concurrent-0-predefined-5/docker (executor_docker.go:834:0s)