fix(official-text): delete nullable for publicationDate

Author: Mihoub2

src/openapi/schemas/officialtexts/officialtext-payload.yml

@@ -30,7 +30,6 @@ properties:
     pattern: '^\d{2,4}-\d{1,4}$'
     nullable: true
   publicationDate:
-    nullable: true
     type: string
     pattern: '((^$)|(^\d{4}$)|(^\d{4}-(0[1-9]|1[0-2]))|(^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])$))'
   signatureDate: