Automatic merge from submit-queue

Fix proxied request-uri to be valid HTTP requests

Fixes #52022, introduced in 1.7. Stringifying/re-parsing the URL masked that the path was not constructed with a leading `/` in the first place.

This makes upgrade requests proxied to pods/services via the API server proxy subresources be valid HTTP requests

```release-note
Fixes an issue with upgrade requests made via pod/service/node proxy subresources sending a non-absolute HTTP request-uri to backends
```