append フィルター（文字列の末尾に追加）

{
  "category": "string",
  "deprecated": false,
  "deprecation_reason": "",
  "description": "",
  "parameters": [],
  "return_type": [
    {
      "type": "string",
      "name": "",
      "description": "",
      "array_value": ""
    }
  ],
  "examples": [
    {
      "name": "",
      "description": "",
      "syntax": "",
      "path": "/products/health-potion",
      "raw_liquid": "{%-  assign path = product.url -%}\n\n{{ request.origin | append: path }}",
      "parameter": false,
      "display_type": "text",
      "show_data_tab": true
    }
  ],
  "summary": "Adds a given string to the end of a string.",
  "syntax": "string | append: string",
  "name": "append"
}