Fixed local storage auth token being retrieved incorrectly

[lauraneto]

I've been using these helpers in the integration tests of my package.
When I was testing V15 locally, I kept getting this error:

SyntaxError: Unexpected non-whitespace character after JSON at position 4

    at ApiHelpers.getRefreshToken (D:\Projects\Umbraco.Community.DeliveryApiExtensions\tests\UmbracoDeliveryApiExtensions.Playwright\node_modules\@umbraco\playwright-testhelpers\lib\helpers\ApiHelpers.ts:205:27)
    at ApiHelpers.refreshAccessToken (D:\Projects\Umbraco.Community.DeliveryApiExtensions\tests\UmbracoDeliveryApiExtensions.Playwright\node_modules\@umbraco\playwright-testhelpers\lib\helpers\ApiHelpers.ts:250:26)
    at Object.umbracoApi (D:\Projects\Umbraco.Community.DeliveryApiExtensions\tests\UmbracoDeliveryApiExtensions.Playwright\node_modules\@umbraco\playwright-testhelpers\lib\helpers\testExtension.ts:11:5)

When I checked the ApiHelpers code, I noticed that several calls were assuming that the auth token would be in index 0 of origins, which wasn't the case for me:

{
  ...
  "origins": [
    {
      "origin": "https://localhost:44363",
      "localStorage": [
        {
          "name": "umb:serverUpgradeCheck",
          "value": "{\"type\":\"None\",\"comment\":\"\",\"url\":\"\",\"expires\":\"2024-11-22T21:02:48.808Z\"}"
        },
        {
          "name": "umb:lastUpgradeCheck",
          "value": "2024-11-15T21:02:48.436Z"
        },
        {
          "name": "umb:userAuthTokenResponse",
          "value": "{\"access_token\":\"...\",\"scope\":\"offline_access\",\"token_type\":\"Bearer\",\"issued_at\":1731704598,\"expires_in\":\"3600\"}"
        }
      ]
    }
  ]
}

This fixes #160.

[andr317c]

Looks good to me!💪