Add note about bug with npm registry

What does this MR do?

In #352962 (closed), there is a bug where the job token does not work with npm packages at the instance level that have dependencies in other projects. It results in a 404. This can be frustrating as a user because you know the packages exist and it's not clear why they are returning as not found. This MR adds a note to the docs to call out the bug to prevent users from running into a wall

Related issues

#352962 (comment 994201279)

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