Improve workaround for phantomJS

Fixup for 793f9307

The phantomJS issue can also appear in other contexts. Thus we set the
environment variable for all executions of "node".
1 job for release-3 in 1 minute and 36 seconds
Status Job ID Name Coverage
  Test
failed #2848
make_test

00:01:36

 
Name Stage Failure
failed
make_test Test
    Can't uninstall 'Pillow'. No files were found to uninstall.
Found existing installation: recommonmark 0.4.0
Not uninstalling recommonmark at /usr/lib/python3/dist-packages, outside environment /builds/stadtgestalten/stadtgestalten/gitlab-ci-build-venv
Can't uninstall 'recommonmark'. No files were found to uninstall.
Successfully installed aiosmtpd-1.2 aiosmtplib-1.1.0 atpublic-1.0 bleach-3.1.0 certifi-2019.9.11 chardet-3.0.4 commonmark-0.9.1 defusedxml-0.6.0 django-2.2.6 django-allauth-0.40.0 django-appconf-1.0.3 django-csp-3.5 django-filter-2.2.0 django-haystack-2.8.1 django-ical-1.7.0 django-imagekit-4.0.2 django-mailbox-4.8.1 django-recurrence-1.10.1 django-taggit-1.1.0 djangorestframework-3.10.3 entrypoints-0.3 feedparser-5.2.1 flake8-3.7.8 html2text-2019.9.26 huey-2.1.3 icalendar-4.0.3 idna-2.8 markdown-2.6.11 mccabe-0.6.1 mdx-unimoji-1.0 oauthlib-3.1.0 pilkit-2.0 pillow-6.2.0 pycodestyle-2.5.0 pyflakes-2.1.1 pymdown-extensions-5.0 python-dateutil-2.8.0 python3-openid-3.1.0 randomcolor-0.4.4.5 raven-6.10.0 recommonmark-0.6.0 redis-3.3.11 requests-2.22.0 requests-oauthlib-1.2.0 rules-2.1 schulze-0.1 sqlparse-0.3.0 translitcodec-0.4.0 urllib3-1.25.6 webencodings-0.5.1 xapian-haystack-2.1.1
$ make app_local_settings
Downloading 'makefilet' ...
make.d/nodejs.mk:13: *** missing separator. Stop.
ERROR: Job failed: exit code 1