additionalItems does not support $ref

[unional]

Describe the bug

The additionalItems should support schema including $ref

{
  "$schema": "http://json-schema.org/draft-07/schema",
  "type": "object",
  "properties": {
    "test": {
      "$ref": "#/definitions/Recur"
    }
  },
  "definitions": {
    "Recur": {
      "type": "array",
      "items": [
        {
          "type": "string",
          "enum": [
            "and"
          ]
        }
      ],
      "additionalItems": {
        "$ref": "#/definitions/Recur"
      }
    }
  }
}

VSCode Json Language Service used to have the same problem and is recently fixed:
microsoft/vscode-json-languageservice#69

So it is working on the json side:

Expected Behavior

schema including $ref should be supported for additionalItems for Tuple Validation:
https://json-schema.org/understanding-json-schema/reference/array.html#id6

Current Behavior

Steps to Reproduce

Environment

• Windows
• Mac
• Linux
• other (please specify)

[evidolob]

Fixed with redhat-developer/yaml-language-server#433