Fix javadoc waring in MongoCryptException (#1504)

Author: stIncMale

mongodb-crypt/src/main/com/mongodb/crypt/capi/MongoCryptException.java

@@ -20,6 +20,8 @@
 
 /**
  * Exception thrown for errors originating in the mongodb-crypt module.
+ *
+ * @serial exclude
  */
 public class MongoCryptException extends RuntimeException {
     private static final long serialVersionUID = -5524416583514807953L;