test: use path.join in async-hooks/test-tlswrap.js

PR-URL: #14319
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>

test/async-hooks/test-tlswrap.js

@@ -5,11 +5,13 @@ if (!common.hasCrypto)
   common.skip('missing crypto');
 
 const assert = require('assert');
+const fs = require('fs');
+const path = require('path');
+const tls = require('tls');
+
 const tick = require('./tick');
 const initHooks = require('./init-hooks');
-const fs = require('fs');
 const { checkInvocations } = require('./hook-checks');
-const tls = require('tls');
 
 const hooks = initHooks();
 hooks.enable();
@@ -19,8 +21,8 @@ hooks.enable();
 //
 const server = tls
   .createServer({
-    cert: fs.readFileSync(common.fixturesDir + '/test_cert.pem'),
-    key: fs.readFileSync(common.fixturesDir + '/test_key.pem')
+    cert: fs.readFileSync(path.join(common.fixturesDir, 'test_cert.pem')),
+    key: fs.readFileSync(path.join(common.fixturesDir, 'test_key.pem'))
   })
   .on('listening', common.mustCall(onlistening))
   .on('secureConnection', common.mustCall(onsecureConnection))