Merge "fix tox python3 overrides"

tox.ini

@@ -4,7 +4,6 @@ minversion = 2.3
 skipsdist = True
 
 [testenv]
-basepython = python3
 setenv = VIRTUAL_ENV={envdir}
          OS_STDOUT_CAPTURE=1
          OS_STDERR_CAPTURE=1
@@ -15,18 +14,23 @@ commands = find {toxinidir} -type f -not -path '{toxinidir}/.tox/*' -not -path '
 deps = -r{toxinidir}/test-requirements.txt
 
 [testenv:venv]
+basepython = python3
 commands = {posargs}
 
 [testenv:flake8]
+basepython = python3
 description = Dummy environment to allow flake8 to be run in subdir tox
 
 [testenv:pep8]
+basepython = python3
 description = Dummy environment to allow pep8 to be run in subdir tox
 
 [testenv:pylint]
+basepython = python3
 description = Dummy environment to allow pylint to be run in subdir tox
 
 [testenv:linters]
+basepython = python3
 whitelist_externals = bash
 commands =
   bash -c "find {toxinidir}        \
@@ -54,6 +58,7 @@ whitelist_externals =
     reno
 
 [testenv:newnote]
+basepython = python3
 # Re-use the releasenotes venv
 envdir = {toxworkdir}/releasenotes
 deps = -r{toxinidir}/doc/requirements.txt