Update login command to not suggest a broken command

[tylerslaton]

Prior this commit, we were suggesting a command that does not work upon successful login:

acorn login acorn.io
# ...
  •  Run "acorn projects acorn.io" to list available projects
  •  Run "acorn project use acorn.io/sangee2004/mytest1" to set default project
  ✔  Login to acorn.io as sangee2004 succeeded

This now looks like:

acorn login acorn.io
# ...
  •  Run "acorn projects" to list available projects
  •  Run "acorn project use acorn.io/sangee2004/mytest1" to set default project
  ✔  Login to acorn.io as sangee2004 succeeded

Checklist

• The title of this PR would make a good line in Acorn's Release Note's Changelog
• The title of this PR ends with a link to the main issue being address in parentheses, like: This is a title (#1216). Here's an example
• All relevant issues are referenced in the PR description. NOTE: don't use GitHub keywords that auto-close issues
• Commits follow contributing guidance
• Automated tests added to cover the changes. If tests couldn't be added, an explanation is provided in the Verification and Testing section
• Changes to user-facing functionality, API, CLI, and upgrade impacts are clearly called out in PR description
• PR has at least two approvals before merging (or a reasonable exception, like it's just a docs change)