Proxy access

When loading "swagger/ui" through proxy I get "Failed to load response data: No resource with given identifier found". Page download swagger.json from the original url. When doing same request with Postman I can see that html is correct.

**To Reproduce**
Steps to reproduce the behavior:
1. add proxy. for example "proxy.com/yourapp"
2. go to "proxy.com/yourapp/swagger/ui
3. See empty page with swagger.json downloaded as a file

**Expected behavior**
I would like to have same view as the original.

**Environment (please complete the following information, if applicable):**
- OS: Windows
- Browsers: edge, chrome, firefox

**Additional context**
Some issues that might be related:
https://github.com/domaindrivendev/Swashbuckle.WebApi/issues/705
https://stackoverflow.com/questions/63072382/webapi-swagger-swashbuckle-cant-access-swagger-ui-when-connecting-through-p

Start by reproducing the proxy request at swagger/ui and compare its response with the original URL and the downloaded swagger.json. Review the extension's Swagger UI and OpenAPI request entry points, using the linked Swashbuckle issue and Stack Overflow report as context. Done means the UI renders through a path such as proxy.com/yourapp and no longer downloads swagger.json as a file.

Written by the indexing model from the issue text.