test: replace fixturesDir with fixtures module

PR-URL: #15840
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: tkarsten

test/parallel/test-global.js

@@ -24,9 +24,9 @@
 
 /* eslint-disable strict */
 const common = require('../common');
+const fixtures = require('../common/fixtures');
 
 const assert = require('assert');
-const path = require('path');
 
 common.globalCheck = false;
 
@@ -40,7 +40,7 @@ assert.strictEqual(baseBar, // eslint-disable-line no-undef
                    'bar',
                    'global.x -> x in base level not working');
 
-const mod = require(path.join(common.fixturesDir, 'global', 'plain'));
+const mod = require(fixtures.path('global', 'plain'));
 const fooBar = mod.fooBar;
 
 assert.strictEqual(fooBar.foo, 'foo', 'x -> global.x in sub level not working');