Revert "Enable SSL_MODE_ENABLE_FALSE_START if jdkCompatibilityMode is false (#10407)" (#10980)

Motivation:

TLS_FALSE_START slightly changes the "flow" during handshake which may cause suprises for the end-user. We should better disable it by default again and later add a way to enable it for the user.

Modification:

This reverts commit 514d349e1f.

Result:

Restore "old flow" during TLS handshakes.

handler/src/main/java/io/netty/handler/ssl/ReferenceCountedOpenSslEngine.java

@@ -348,8 +348,7 @@ public class ReferenceCountedOpenSslEngine extends SSLEngine implements Referenc
                 }
 
                 if (!jdkCompatibilityMode) {
-                    SSL.setMode(ssl, SSL.getMode(ssl) | SSL.SSL_MODE_ENABLE_PARTIAL_WRITE
-                            | SSL.SSL_MODE_ENABLE_FALSE_START);
+                    SSL.setMode(ssl, SSL.getMode(ssl) | SSL.SSL_MODE_ENABLE_PARTIAL_WRITE);
                 }
 
                 // setMode may impact the overhead.