[ci/fix] update ci to fix env issues

The nix-env used for CI is being poluted by gitlab CI environ variables,
which ends up crashing argo_nodeos_config.

The real fix would be probably involve figuring out what kind of env
variable value crashes the whole thing and fixing our wrapping logic,
but at the same time, there's no reason for nix to use the CI env in the
first place.

This also resets the CI pointers to 'base'/'basic.yaml'.
13 jobs for minimize-zmq-threads in 5 minutes and 46 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #18450
integration
containers.build

00:00:07

passed #18451
integration
libnrm.build

00:00:03

passed #18452
integration
nrm.build

00:00:08

 
  Test
passed #18458
integration
Hello.test

00:00:09

passed #18459
knl
KNL-Hello.test

00:00:39

passed #18457
knl
KNL-Listen.test

00:00:42

passed #18455
knl
KNL-Perfwrapper.test

00:00:41

passed #18453
knl
KNL-Power.test

00:00:39

passed #18460
knl
KNL-STREAM.test

00:00:41

passed #18456
integration
Listen.test

00:00:11

passed #18454
integration
Perfwrapper.test

00:00:12

passed #18461
rapl
py.test

00:01:04

 
  Style
passed #18462
flake8

00:01:03