task.py: Fix potential security issue

We take care that the window provided is actually a nucleic sequence.
It prevents people from trying to inject something else
12 jobs for feature-s/fix-grep-reads in 26 minutes and 19 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test Tools
passed #1172632
test_tools

00:00:11

 
  Test Quality
failed #1172633
allowed to fail
code_quality

00:00:05

 
  Test Unit
passed #1172641
web
test_server_unit

00:00:25

failed #1172634
web
test_server_unit

00:00:02

 
  Deploy Review
passed #1172635
deploy_review_server

00:02:13

passed #1172636
manual
stop_deploy_review_server

00:00:51

 
  Test Functional
passed #1172637
x86_64 docker
ff32-server-functional

00:07:42

passed #1172839
docker x86_64
ff45-server-functional

00:07:50

failed #1172638
x86_64 docker
ff45-server-functional

00:09:36

 
  Test Tutorial Server
passed #1172956
web-pandoc
server_tutorial_server

00:06:59

failed #1172864
web-pandoc
server_tutorial_server

00:11:23

failed #1172639
web-pandoc
server_tutorial_server

00:12:04

 
Name Stage Failure
failed
code_quality Test Quality
$ function propagate_env_vars() { # collapsed multi-line command
$ docker pull --quiet "$CODE_QUALITY_IMAGE"
unknown flag: --quiet
See 'docker pull --help'.
Uploading artifacts...
Runtime platform arch=386 os=linux pid=18054 revision=58272c27 version=12.7.0
WARNING: gl-code-quality-report.json: no matching files
ERROR: No files to upload
ERROR: Job failed: exit status 1