`wp_get_post_revisions()` should have a default `orderby` of `date ID` to tie-break rapidly added revisions - namely, when unit tests are run. There is a test that occasionally fails when running all tests, and always fails when running `phpunit tests/phpunit/tests/post/revisions.php `. This fixes that.

Fixes #26042.


Built from https://develop.svn.wordpress.org/trunk@27184


git-svn-id: http://core.svn.wordpress.org/trunk@27044 1a063a9b-81f0-0310-95a4-ce76da25c4cd