Merge "fix tox python3 overrides"

tox.ini

@@ -27,6 +27,7 @@ commands =
      doc8 -e '' security-threat-analysis
 
 [testenv:checkbuild]
+basepython = python3
 commands =
   # Build and copy RST Guides
   {toxinidir}/tools/build-all-rst.sh
@@ -34,6 +35,7 @@ commands =
   openstack-indexpage publish-docs
 
 [testenv:publishdocs]
+basepython = python3
 # Prepare all documents so that they can get published on
 # docs.openstack.org with just copying publish-docs/* over.
 commands =
@@ -41,10 +43,12 @@ commands =
   {toxinidir}/tools/build-all-rst.sh
 
 [testenv:checklang]
+basepython = python3
 whitelist_externals = doc-tools-check-languages
 commands = doc-tools-check-languages doc-tools-check-languages.conf test all
 
 [testenv:buildlang]
+basepython = python3
 # Run as "tox -e buildlang -- $LANG"
 whitelist_externals =
     doc-tools-check-languages
@@ -55,6 +59,7 @@ commands =
     bash -c "find security-guide -type f -regex '.*\.pot?' -print0|xargs -0 -n 1 msgfmt --check-format -o /dev/null"
 
 [testenv:publishlang]
+basepython = python3
 whitelist_externals = doc-tools-check-languages
 commands = doc-tools-check-languages doc-tools-check-languages.conf test all
 
@@ -65,6 +70,7 @@ commands =
   {toxinidir}/tools/build-all-rst.sh
 
 [testenv:generatepot-rst]
+basepython = python3
 # Generate POT files for translation, needs {posargs} like:
 # tox -e generatepot-rst -- security-guide
 commands = {toxinidir}/tools/generatepot-rst.sh {posargs}