Pathfinder does not work when there are variables in the server url

[mjphaynes]

I came across this when using the eBay OpenAPI spec, see: https://developer.ebay.com/api-docs/sell/inventory/resources/methods

The server url has the following format:

{
  "servers": [
    {
      "url": "https://api.ebay.com{basePath}",
      "description": "Production",
      "variables": {
        "basePath": {
          "default": "/sell/inventory/v1"
        }
      }
    }
  ],
}

But the code to get the server url does not replace the variables:

openapi-psr7-validator/src/PSR7/PathFinder.php

Line 190 in a665e22

rtrim((string) parse_url($server->url, PHP_URL_PATH), '/'),

So end up with the error: OpenAPI spec contains no such operation [/sell/inventory/v1/inventory_item/sku]