test: fix exec-any-shell test for powershell

When giving 'echo foo bar' to powershell, the result contains a new line like: foo bar This commit enables to test with poweshell correctly.
nodejs · tkamenoko · Jul 21, 2018 · Jul 21, 2018 · Jul 21, 2018 · Jul 23, 2018
commit 6b9b090d6914b9555ce2f3e22b0a62d8c8aa7c06
diff --git a/test/parallel/test-child-process-exec-any-shells-windows.js b/test/parallel/test-child-process-exec-any-shells-windows.js
@@ -12,7 +12,7 @@ if (!common.isWindows)
 const test = (shell) => {
   cp.exec('echo foo bar', { shell: shell }, (error, stdout, stderror) => {
     assert.ok(!error && !stderror);
-    assert.ok(stdout.startsWith('foo bar'));
+    assert.ok(stdout.includes('foo') && stdout.includes('bar'));
   });
 };