Resolve TMSS-241

Closes TMSS-241

SAS/TMSS/src/tmss/tmssapp/models/specification.py

@@ -151,7 +151,7 @@ class Flag(AbstractChoice):
 
 
 class PeriodCategory(AbstractChoice):
-    """Defines the model and predefined list of possible project categories to be used in Project.
+    """Defines the model and predefined list of possible period categories to be used in Project.
         The items in the Choices class below are automagically populated into the database via a data migration."""
 
     class Choices(Enum):
@@ -168,7 +168,7 @@ class ProjectCategory(AbstractChoice):
         REGULAR = "regular"
         USER_SHARED_SUPPORT = "user_shared_support"
         COMMISSIONING = "commissioning"
-        DOT = "ddt"
+        DDT = "ddt"
         TEST = "test"