Deprecate CGLIB

It's unmaintained and does not work with JDK 17.
Users should use Javassist instead.

Author: harawata

src/main/java/org/apache/ibatis/executor/loader/cglib/CglibProxyFactory.java

@@ -41,7 +41,9 @@
 
 /**
  * @author Clinton Begin
+ * @deprecated Since 3.5.10, use Javassist instead.
  */
+@Deprecated
 public class CglibProxyFactory implements ProxyFactory {
 
   private static final String FINALIZE_METHOD = "finalize";

src/main/java/org/apache/ibatis/executor/loader/cglib/CglibSerialStateHolder.java

@@ -24,7 +24,9 @@
 
 /**
  * @author Eduardo Macarron
+ * @deprecated Since 3.5.10, use Javassist instead.
  */
+@Deprecated
 class CglibSerialStateHolder extends AbstractSerialStateHolder {
 
   private static final long serialVersionUID = 8940388717901644661L;