Removed non-boolean required references in doc.

Signed-off-by: Andre Araujo <araujo@cloudera.com>

Author: asdaraujo

plugins/modules/df_service.py

@@ -40,15 +40,13 @@
       - The environment name can also be provided, instead of the CRN
       - Required when I(state=present)
     type: str
-    required: Conditional
     aliases:
       - name
   df_crn:
     description: 
       - The CRN of the DataFlow Service, if available
       - Required when I(state=absent)
     type: str
-    required: Conditional
   state:
     description:
       - The declarative state of the Dataflow Service