Remove duplicate YAML loading of environment variables.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

mayan/apps/smart_settings/classes.py

@@ -151,7 +151,7 @@ class Setting(object):
         if environment_value:
             self.environment_variable = True
             try:
-                self.raw_value = yaml.safe_load(environment_value)
+                self.raw_value = environment_value
             except yaml.YAMLError as exception:
                 raise type(exception)(
                     'Error interpreting environment variable: {} with '