Do not add console if already present

Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/settings_example.py

@@ -378,7 +378,8 @@ LOGGING = {
 }
 
 # Logging of management commands to console
-if os.environ.get('DJANGO_IS_MANAGEMENT_COMMAND', False):
+if (os.environ.get('DJANGO_IS_MANAGEMENT_COMMAND', False)
+        and 'console' not in LOGGING['loggers']['weblate']['handlers']):
     LOGGING['loggers']['weblate']['handlers'].append('console')
 
 # Machine translation API keys