test: run test-setproctitle where supported

Setting the process title has been enabled in libuv on AIX and z/OS. The
latest level of libuv skips only skips testing of uv_set_process_title
when __sun is #defined.

This change simplifies the skip test so the test is only skipped when
common.isSunOS is true to match libuv. Skip running the `ps` part of the
test on Windows.

PR-URL: #11416
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>

Author: hhellyer

test/parallel/test-setproctitle.js

@@ -3,7 +3,7 @@
 const common = require('../common');
 
 // FIXME add sunos support
-if (!(common.isFreeBSD || common.isOSX || common.isLinux)) {
+if (common.isSunOS) {
   console.log(`1..0 # Skipped: Unsupported platform [${process.platform}]`);
   return;
 }
@@ -21,6 +21,10 @@ assert.notStrictEqual(process.title, title);
 process.title = title;
 assert.strictEqual(process.title, title);
 
+// Test setting the title but do not try to run `ps` on Windows.
+if (common.isWindows)
+  return;
+
 exec(`ps -p ${process.pid} -o args=`, function callback(error, stdout, stderr) {
   assert.ifError(error);
   assert.strictEqual(stderr, '');