Provide better message for 401 codes

[andrei-epure-sonarsource]

The following error message appears often on the community.:

The token you provided doesn’t have sufficient rights to check license

What it does

15:54:48.927 Downloading from http://SQ/api/server/version...
15:54:48.958 Checking validity of server license
15:54:48.958 Downloading from http://SQ/api/editions/is_valid_license...

However, if you look at the root causes of the community posts, it can be different issues, for example: user not providing a valid token at all (The problem was that I was using same name for Project and Token name.) - we can detect that.

Also, if the token is not good for authentication, we shouldn't give a message about the license.

In this whisper I suggested

In any case, if there’s an issue with authentication, we should provide a link to documentation around how to generate a token?

and @ganncamp said:

I found the particular error message in question in the Scanner for MSBuild repo & I’ve never seen this particular message before, i.e. I’ve never seen it outside the .NET context

[andrei-epure-sonarsource]

additional feedback https://discuss.sonarsource.com/t/sonarscanner-for-net-call-for-the-is-valid-license-end-point/11201/6

[costin-zaharia-sonarsource]

Link to internal thread related to using the license API in the scanner: https://discuss.sonarsource.com/t/usage-of-api-editions-is-valid-license-in-net-scanner/13670