[3.1.4/4.2.5/5.1.8/6.2.2/7.4.8/8.0.6/9.0.7/10.2.3 regression] `minimatch("a", "a/**", { partial: true })` incorrectly returns `false`

In 10.2.2, `minimatch("a", "a/**", { partial: true })` returned `true`, but in 10.2.3 it now incorrectly returns `false`.

`git bisect` shows this regression was introduced by 0bf499aa45f5059b56809cc3b75ff3eafeb8d748.

The same regression was introduced in 3.1.3→3.1.4, 4.2.4→4.2.5, 5.1.7→5.1.8, 6.2.1→6.2.2, 7.4.7→7.4.8, 8.0.5→8.0.6, and 9.0.6→9.0.7.