BREAKING CHANGE(config): remove dangerous auth configs

[wraithgar]

Summary

Config like bare _auth is confusing, and should be removed. Users should tie it to a registry like _authToken

Exit Criteria

• Remove _auth config
• Remove _authToken config
• Remove username config
• Remove password config
• Remove email config this is an unscoped only value today and should be removed in the future, no changes were made
• Add documentation in an existing page &/or net-new page about the scoping of sensitive configs to the corresponding registry (ie. auth settings)