Using let's properly in inline comments lets us move on to more pressing matters of inline documentation.

Props trepmal.
Fixes #30570.

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git-svn-id: http://core.svn.wordpress.org/trunk@30693 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Unit Tests: The `test_set_allowed_incompatible_sql_mode()` test tries to set the `NO_ZERO_DATE` sql mode, which was removed in MySQL 5.7. This causes the test to incorrectly fail when run against MySQL 5.7.


Built from https://develop.svn.wordpress.org/trunk@30704


git-svn-id: http://core.svn.wordpress.org/trunk@30694 1a063a9b-81f0-0310-95a4-ce76da25c4cd