Postman collection with variable for the file name

collection.json

{
	"info": {
		"_postman_id": "d7e89525-371a-4d96-8683-ea3d9a40c0ca",
		"name": "Upload",
		"schema": "https://schema.getpostman.com/json/collection/v2.1.0/collection.json"
	},
	"item": [
		{
			"name": "https://hookb.in/OeZner0EOYTyVylW6bWj",
			"event": [
				{
					"listen": "prerequest",
					"script": {
						"id": "38f6fef9-bee5-429f-b030-7a272315bfc0",
						"exec": [
							"pm.globals.set(\"fileName\", \"random.js\");"
						],
						"type": "text/javascript"
					}
				}
			],
			"request": {
				"method": "POST",
				"header": [],
				"body": {
					"mode": "formdata",
					"formdata": [
						{
							"key": "file",
							"type": "file",
							"src": "{{fileName}}"
						}
					]
				},
				"url": {
					"raw": "https://hookb.in/OeZner0EOYTyVylW6bWj",
					"protocol": "https",
					"host": [
						"hookb",
						"in"
					],
					"path": [
						"OeZner0EOYTyVylW6bWj"
					]
				}
			},
			"response": []
		}
	]
}