Fix tox.ini with tox4

Change-Id: I430d9e1852e54be6c75e05b82ed245cafac08a57
diff --git a/tox.ini b/tox.ini
index ff50b9d..678e9db 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,7 +1,6 @@
 [tox]
 minversion = 3.18.0
 envlist = pep8
-skipsdist = True
 ignore_basepython_conflict = True
 
 [testenv]
@@ -20,10 +19,10 @@
 
 [testenv:pep8]
 commands =
-  sh ./tools/misc-sanity-checks.sh
+  bash ./tools/misc-sanity-checks.sh
   flake8
 allowlist_externals =
-  sh
+  bash
 
 [testenv:venv]
 commands = {posargs}