fix(skel): Skip placeholder test

Author: kriskowal

packages/skel/test/index.test.js

@@ -1,5 +1,5 @@
 import test from '@endo/ses-ava/prepare-endo.js';
 
-test('placeholder', async t => {
+test.skip('placeholder', async t => {
   t.fail('TODO: add tests');
 });