Fixed issue: pass_env values cannot contain whitespace, use comma to have multiple

values in a single line

https://github.com/kubernetes-client/python/actions/runs/4001147429/jobs/6867090020

Author: yliaog

Diff for: tox.ini

@@ -4,7 +4,7 @@ envlist =
    py3{6,7,8,9}-functional
 
 [testenv]
-passenv = TOXENV CI TRAVIS TRAVIS_*
+passenv = TOXENV,CI,TRAVIS,TRAVIS_*
 usedevelop = True
 install_command = pip install -U {opts} {packages}
 deps = -r{toxinidir}/test-requirements.txt