Remove unused constant

atst/utils/localization.py

@@ -1,13 +1,10 @@
 import yaml
-import os
 from functools import lru_cache
 import math
 from gettext import ngettext
 from flask import current_app as app
 from atst.utils import getattr_path
 
-ENV = os.getenv("FLASK_ENV", "dev")
-
 
 class LocalizationInvalidKeyError(Exception):
     def __init__(self, key, variables):