Move log in section earlier in setup steps

What does this MR do?

• In !33443 (merged) we learned that there is an issue with the LB health check endpoint because the /users/sign_in page wasn't available yet. The instances redirect to /users/password/.. until the root password is set on first log in.
• A fix for this is to set the root password before we create the custom AMI used in the launch configuration for the auto scaling group. This way the password is saved to the database and when the instances launch GitLab presents the /users/sign_in endpoint used in the LB health check.
• Also changes authorization to authentication as that is the correct term in this instance.

Related issues

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