Add a 'lil more logging

2 jobs for master in 2 seconds (queued for 32 seconds)
Status Job ID Name Coverage
  Test
failed #456
test

00:00:02

 
  Build
skipped #457
build
 
Name Stage Failure
failed
test Test
   54b61a3..fabad29  master     -> origin/master
Checking out fabad29e as master...
Skipping Git submodules setup
Checking cache for default...
time="2020-04-04T22:43:34+08:00" level=error msg="Docker executor: prebuilt image helpers will be loaded from /var/lib/gitlab-runner."
Successfully extracted cache
$ rustc --version
bash: line 78: rustc: command not found
ERROR: Job failed: exit status 1