[Schema Inaccuracy] code-scanning-alert-dismissed-reason enum contains null but is already nullable

[hfhbd]

Schema Inaccuracy

You should not include the null value in the enum if the enum itself is nullable, like you do in other enum descriptions, eg state_reason.

Expected

"code-scanning-alert-dismissed-reason": {
        "type": "string",
        "description": "**Required when the state is dismissed.** The reason for dismissing or closing the alert.",
        "nullable": true,
        "enum": [
          "false positive",
          "won't fix",
          "used in tests"
        ]
      }