Merge branch 'str-to-string' into 'master'

str to string in user configuration field types

See merge request !1620

arkindex/dataimport/serializers/workers.py

@@ -47,7 +47,7 @@ class WorkerSerializer(WorkerLightSerializer):
 class UserConfigurationFieldType(Enum):
     Int = 'int'
     Float = 'float'
-    String = 'str'
+    String = 'string'
     Enum = 'enum'