Hide the fact that a space does exist but you don't have access

[tareefk]

From Mine:

• At this point I thought about testing to see if I can access info on spaces that are not tied to my RStudio email address, which I assume is how Sean created the credentials, and as expected, I get a Forbidden HTTP 403 error. Should I instead get a not found error though? Does forbidden indicate that such a space exists, I'm not allowed in? I'm thinking about private GitHub repos, if you go to one you're not a part of, you don't even get to know it exists, it just says page not found.

[tareefk]

I have taken a crack at different messaging and a cleaner returned error code.