Set default timezone as UTC

The previous setting of "Etc/UTC" appears to no longer be valid in certain
circumstances. This was causes tests to fail on user settings because the
provided default was invalid. "UTC" should be more uniformly recognized so
hopefully this does not have any downstream effects.

Closes #203

.ebextensions/babybuddy.config

@@ -2,7 +2,7 @@ option_settings:
   aws:elasticbeanstalk:application:environment:
     DJANGO_SETTINGS_MODULE: babybuddy.settings.eb
     SECRET_KEY: CHANGETOSOMETHINGRANDOM
-    TIME_ZONE: Etc/UTC
+    TIME_ZONE: UTC
   aws:elasticbeanstalk:container:python:staticfiles:
     '/static/': 'static/'
   aws:elasticbeanstalk:container:python:

README.md

@@ -409,7 +409,7 @@ See also [Django's documentation on the SECRET_KEY setting](https://docs.djangop
 
 ### `TIME_ZONE`
 
-*Default: Etc/UTC*
+*Default: UTC*
 
 The default time zone to use for the instance. See [List of tz database time zones](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones)
 for all possible values. This value can be overridden per use from the user

app.json

@@ -33,7 +33,7 @@
         },
         "TIME_ZONE": {
             "description": "Sets the instance default time zone.",
-            "value": "Etc/UTC"
+            "value": "UTC"
         }
     },
     "scripts": {

babybuddy/settings/base.py

@@ -139,7 +139,7 @@ LOGOUT_REDIRECT_URL = '/login/'
 
 USE_TZ = True
 
-TIME_ZONE = os.environ.get('TIME_ZONE') or 'Etc/UTC'
+TIME_ZONE = os.environ.get('TIME_ZONE') or 'UTC'
 
 # Internationalization
 # https://docs.djangoproject.com/en/3.0/topics/i18n/

babybuddy/tests/tests_forms.py

@@ -31,7 +31,7 @@ class FormsTestCase(TestCase):
             'email': 'user@user.user',
             'dashboard_refresh_rate': '',
             'language': 'en',
-            'timezone': timezone.get_default_timezone_name(),
+            'timezone': 'UTC',
             'next': '/user/settings/'
         }