fix: add signatureFlow to ValidateFile schema in openapi.json

Complete the OpenAPI schema update by adding signatureFlow field to
the ValidateFile schema definition.

This was manually corrected after the initial automated update.

Signed-off-by: Vitor Mattos <[email protected]>

Author: vitormattos

openapi.json

@@ -862,7 +862,6 @@
                     "status",
                     "statusText",
                     "nodeId",
-                    "signatureFlow",
                     "totalPages",
                     "size",
                     "pdfVersion",
@@ -896,10 +895,6 @@
                         "format": "int64",
                         "minimum": 0
                     },
-                    "signatureFlow": {
-                        "type": "integer",
-                        "format": "int64"
-                    },
                     "totalPages": {
                         "type": "integer",
                         "format": "int64",