test: skipIfInspectorDisabled cluster-inspect-brk

When configured --without-ssl the inspect-brk option will not be
available and the process will exit with a exit value of 9 "Invalid
Argument/Bad option".

This commit adds a skipIfInspectorDisabled check since --without-ssl
implies that no inspector support is build as well.

PR-URL: nodejs#12757
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

test/sequential/test-cluster-inspect-brk.js

@@ -1,5 +1,6 @@
 'use strict';
 const common = require('../common');
+common.skipIfInspectorDisabled();
 
 // A test to ensure that cluster properly interoperates with the
 // --inspect-brk option.