If the hole is small enough to allow, put a small drop of cyanoacrylate "Super Glue"-"Crazy Glue" to span the gap.
Alternately, using super glue to attach a small drum-skin patch will work for slightly larger holes. You can sometimes make the patch by cutting a tiny patch from an inconspicuous edge of the skin beyond the area needed for tensioning. If not, then get a head that is similar thickness and cut as many as you wish.
USE TWEEZERS to place the patch after placing a tiny bit of the glue around the hole...enough to distribute the glue across the whole patch, but not so much that it leaks all over from behind the patch.
Work carefully. Good luck.