test for _delete_option_fresh_site

Trac ticket: https://core.trac.wordpress.org/ticket/57191

Looking at this, why do we need to retrieve the option's value prior to checking? Can't we just use '0' instead since that should be the value?

Ah, I see the resolved conversation now. To make sure I understand, the concern is that the value is potentially not '0' when the test method starts, and if there is a failure, it won't be returned to the originally expected value

[swissspidy]

In 57729:

Build/Test Tools: Add unit tests for _delete_option_fresh_site().

Props pbearne, costdev, desrosj.
Fixes #57191.

Committed in https://core.trac.wordpress.org/changeset/57729