Config CircleCI workflow (#22590)

* Add mypyrc to control typing check, add mypy to circle

* Add translation upload circlci job

script/translations_upload

@@ -26,7 +26,8 @@ LANG_ISO=en
 
 CURRENT_BRANCH=$(git rev-parse --abbrev-ref HEAD)
 
-if [ "${CURRENT_BRANCH-}" != "dev" ] && [ "${TRAVIS_BRANCH-}" != "dev" ] ; then
+# Check Travis and CircleCI environment as well
+if [ "${CURRENT_BRANCH-}" != "dev" ] && [ "${TRAVIS_BRANCH-}" != "dev" ] && [ "${CIRCLE_BRANCH-}" != "dev" ]; then
   echo "Please only run the translations upload script from a clean checkout of dev."
   exit 1
 fi