test: do not assume tls handshake order

Test assumed that server handshake event happened before client destroys
the connection, but that is not guaranteed. Also, the test was closing
the TCP connection 3 times, effectively:

1. on the server side, right after TLS connection occurs (if it does)
2. on the client side, internal to tls, when the cert is rejected
3. again on the client side, in the error event which is emitted by
   the internal tls destroy from 2

This is too often, and the dependency on 1 occuring is fragile.

Remove 1 and 3 so that the test will fail unless 2 occurs.

test/parallel/test-tls-friendly-error-message.js

@@ -31,14 +31,15 @@ const tls = require('tls');
 const key = fixtures.readKey('agent1-key.pem');
 const cert = fixtures.readKey('agent1-cert.pem');
 
-tls.createServer({ key, cert }, common.mustCall(function(conn) {
-  conn.end();
+tls.createServer({ key, cert }).on('connection', common.mustCall(function() {
+  // Server only receives one TCP connection, stop listening when that
+  // connection is destroyed by the client, which it should do after the cert is
+  // rejected as unauthorized.
   this.close();
 })).listen(0, common.mustCall(function() {
   const options = { port: this.address().port, rejectUnauthorized: true };
   tls.connect(options).on('error', common.mustCall(function(err) {
     assert.strictEqual(err.code, 'UNABLE_TO_VERIFY_LEAF_SIGNATURE');
     assert.strictEqual(err.message, 'unable to verify the first certificate');
-    this.destroy();
   }));
 }));