[CI] set PYWIKIBOT_NO_USER_CONFIG environment variable within shell

setenv is not respected in tox;
therefore set this environment variable in run-tests.sh

Bug: T349599
Change-Id: If7fb753ca22721c381cc7817708562d99d2b175e
---
M run-tests.sh
M tox.ini
2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/run-tests.sh b/run-tests.sh
index 2941b01..edaf9ae 100755
--- a/run-tests.sh
+++ b/run-tests.sh
@@ -11,4 +11,8 @@
 done
 
 cd $1/pywikibot-build
+
+# T349599: setenv is not respected in tox;
+# therefore set this environment variable here
+export PYWIKIBOT_NO_USER_CONFIG=2
 python -m unittest -v tests/l10n_tests.py
diff --git a/tox.ini b/tox.ini
index 054bd24..732623c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -10,10 +10,6 @@
 envlist = py37
 
 [testenv]
-setenv =
-    VIRTUAL_ENV={envdir}
-    PYWIKIBOT_NO_USER_CONFIG=2
-
 commands = ./run-tests.sh {envtmpdir}
 
 deps =

