[Content]: Clarify that Track API is entirely unauthenticated

[FirstWhack]

What article on segment.com/docs is affected?

https://segment.com/docs/connections/sources/catalog/libraries/server/http-api/#regional-configuration

What part(s) of the article would you like to see updated?

The article states:

Authenticate to the Tracking API by sending your project’s Write Key along with a request. Authentication uses HTTP Basic Auth, which involves a username:password that is base64 encoded and prepended with the string Basic.

This is not really true as the API always responds 200 OK even if no auth header is provided at all. We are building a new Source and this information was confusing to us because it implies we can test the write key/authentication when the user is configuring the integration on our side.

As a side note/feature request, an API which returns 401 when provided a bad write key (or no auth) would be valuable so that our users can "test integration" during configuration.

Additional information

[github-actions]

This issue is stale because it has been open 60 days with no activity.