modernize gitlab CI script

2 jobs for master in 4 minutes and 52 seconds
Status Job ID Name Coverage
  Test
failed #238271234
test

00:04:52

failed #238271235
test:8.7

00:04:29

 
Name Stage Failure
failed
test Test
Traceback (most recent call last):
File "/opt/sage/src/bin/sage-runtests", line 127, in <module>
err = DC.run()
File "/opt/sage/local/lib/python2.7/site-packages/sage/doctest/control.py", line 1147, in run
self.test_safe_directory()
File "/opt/sage/local/lib/python2.7/site-packages/sage/doctest/control.py", line 618, in test_safe_directory
.format(os.getcwd()))
RuntimeError: refusing to run doctests from the current directory '/builds/videlec/veerer' since untrusted users could put files in this directory, making it unsafe to run Sage code from
ERROR: Job failed: exit code 1
failed
test:8.7 Test
make[3]: Leaving directory '/home/sage/sage/build/make'
make[2]: Leaving directory '/home/sage/sage/build/make'

real 0m7.266s
user 0m4.132s
sys 0m1.471s
Sage build/upgrade complete!
make[1]: Leaving directory '/home/sage/sage'
ERROR: Job failed: exit code 1