Update Spectral rules and fix eBL required properties

Author: HenrikHL

.stoplight/styleguide.json

@@ -973,6 +973,8 @@ components:
     TransportCall:
       title: Transport Call
       type: object
+      description: |
+        A transportCall in the schedule. A transportCall can be either just a Port or further specified as a terminalCall.
       required:
         - transportCallReference
         - carrierImportVoyageNumber

cs/v1/CS_v1.0.3.yaml

@@ -10264,6 +10264,9 @@ components:
           example: AMENDMENT_RECEIVED
         amendedTransportDocument:
           $ref: '#/components/schemas/TransportDocument'
+      required:
+        - amendedTransportDocumentStatus
+        - amendedTransportDocument
 
     ############
     # Transports