tls: use correct class name in deprecation message

`tls.Socket` does not exist, and the deprecation message
should refer to `tls.TLSSocket` (like the documentation
for the deprecation message already does).

PR-URL: nodejs#17561
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Jon Moss <me@jonathanmoss.me>
Reviewed-By: Timothy Gu <timothygu99@gmail.com>
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

lib/_tls_legacy.js

@@ -949,6 +949,6 @@ module.exports = {
   createSecurePair:
     internalUtil.deprecate(createSecurePair,
                            'tls.createSecurePair() is deprecated. Please use ' +
-                           'tls.Socket instead.', 'DEP0064'),
+                           'tls.TLSSocket instead.', 'DEP0064'),
   pipe
 };

test/parallel/test-tls-legacy-deprecated.js

@@ -9,7 +9,7 @@ const tls = require('tls');
 
 common.expectWarning(
   'DeprecationWarning',
-  'tls.createSecurePair() is deprecated. Please use tls.Socket instead.'
+  'tls.createSecurePair() is deprecated. Please use tls.TLSSocket instead.'
 );
 
 assert.doesNotThrow(() => tls.createSecurePair());