Remove locale overrides form tox template

Change Iad912181bc00827908887d45a448f559d5083194 removed them from
tox.ini, so we should remove them from tox-tmpl.ini, too, so that
they don't reappear when tox.ini gets regenerated by toxgen.

Change-Id: Ib3544a95cf1e17230fea9b5699a9b84adb09d973

tox-tmpl.ini

@@ -10,9 +10,6 @@ skipsdist = True
 usedevelop = True
 install_command = pip install {opts} {packages}
 setenv = VIRTUAL_ENV={envdir}
-         LANG=en_US.UTF-8
-         LANGUAGE=en_US:en
-         LC_ALL=C
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
        alembic>=0.4.1