Cannot add separate files from the same GitLab snippet

### Steps to reproduce

* [Create a snippet](https://gitlab.com/-/snippets) on GitLab
* Add two different files/Brave Goggles to it
* Get the raw links for each file and use them on the [Create your own Goggles](https://search.brave.com/goggles/create) page

### Result
When you try to submit the second file, Brave just reloads the first one.

### Expected result
Since it is possible to have multiple files in the same GitLab snippet, Brave should look at the full URL for each file instead of relying only on the snippet ID.

Start at the Create your own Goggles page and reproduce the issue with two raw links from one GitLab snippet. Trace how each URL is identified during submission; done means submitting the second file loads that file rather than reusing the first.

Written by the indexing model from the issue text.