Update benchmark tests to use `enablePlaceholders` helper

What does this MR do?

Updates the benchmark tests to use the enablePlaceholders test helper.

This is a follow up to !458 (comment 655605663).

TODO

• I added unit tests or they are not required
• I added acceptance tests or they are not required
• I added documentation (or it's not required)
• I followed code review guidelines
• I followed Go Style guidelines