When using the X-Wikimedia-Debug header or the WikimediaDebug extension, requests to api.wikimedia.org seem to get routed directly to mw-debug API servers without going through the REST Gateway.
This has the unfortunate side-effect of breaking change testing with X-W-D that rely on client-side calls to `api.wikimedia.org`.
```
# XWD with Origin hits mw-debug directly and gets a mediawiki 404
❯ curl -s -I -H 'X-Wikimedia-Debug: backend=k8s-mwdebug' -H 'Origin: meta.wikimedia.org' https://api.wikimedia.org/service/lw/specs/openapi.yaml | grep -e 'HTTP\|server:'
HTTP/2 404
server: mw-debug.eqiad.pinkunicorn-6b7fbd968c-2n2vm
# XWD without Origin hits mw-debug directly and gets a mediawiki 404
❯ curl -s -I -H 'X-Wikimedia-Debug: backend=k8s-mwdebug' https://api.wikimedia.org/service/lw/specs/openapi.yaml | grep -e 'HTTP\|server:'
HTTP/2 404
server: mw-debug.eqiad.pinkunicorn-6b7fbd968c-2n2vm
# No XWD hits the Apache backend service through the rest-gateway
❯ curl -s -I https://api.wikimedia.org/service/lw/specs/openapi.yaml | grep -e 'HTTP\|server:'
HTTP/2 200
server: Apache/2.4.67 (Debian)
# Same with an Origin
❯ curl -s -I -H 'Origin: meta.wikimedia.org' https://api.wikimedia.org/service/lw/specs/openapi.yaml | grep -e 'HTTP\|server:'
HTTP/2 200
server: Apache/2.4.67 (Debian)
```
From {T430600}:
>
> Steps to replicate the issue (include links if applicable):
>
> Make sure the WikimediaDebug extension is installed, but not turned on
> Visit https://api.wikimedia.org/service/linkrecommendation/v1/linkrecommendations/wikipedia/en/Apple
> Turn on WikimediaDebug
> Visit https://api.wikimedia.org/service/linkrecommendation/v1/linkrecommendations/wikipedia/en/Apple again
>
> What happens?:
>
> The first load should show some JSON.
>
> The second load will 301 redirect to https://www.mediawiki.org/wiki/Wikimedia_APIs
>
> Further loads of that URL will have the 301 cached for about an hour.
>
> What should have happened instead?:
>
> No redirect should happen.
Investigate, and maybe find a way to have XWD API requests hit the `rest-gateway` and *then* be routed to `mw-debug` backends when appropriate, or normal production backends for non MediaWiki APIs.
As a quick fix, add an exception to `modules/profile/files/trafficserver/x-wikimedia-debug-routing.lua` that does not remap the `host:port` when the original host is api.wikimedia.org.