feat(auth): Support DSN auth for the API client

[evanpurkhiser]

This is in support of #1537

Explicitly does not add this as a global cli parameter

[evanpurkhiser]

Should I add a changelog entry?

[kamilogorek]

We usually generate changelog automatically based on the commit messages, and those are nice so far so you should be fine without doing this by hand. You can also edit minor PRs, like the one about wording change and add #skip-changelog to the description, which will exclude it from the changelog (even after it was already merged).