Adjust tests for test localhost to drive off the config value instead

What does this MR do and why?

Adjust tests for test localhost to drive off the config value instead

• use the default configs instead of hardcoding localhost
• see gitlab-development-kit!3471 (comment 1658597076)

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #428203 (closed)