Exception on altering DATE fields with malformed default value [DBZ-3511]

Migrated from [DBZ-3511](https://issues.redhat.com/browse/DBZ-3511)

When altering MySQL with query
{code:java}
ALTER TABLE test_table_1 ALTER COLUMN data_type_DATE SET DEFAULT 123{code}
Connector fails with message
{code:java}
connect_1 | 2021-04-29 11:40:02,435 ERROR || WorkerSourceTask{id=mysql-connector-0} Task threw an uncaught and unrecoverable exception [org.apache.kafka.connect.runtime.WorkerTask] connect_1 | org.apache.kafka.connect.errors.ConnectException: Text '123' could not be parsed at index 0 connect_1 | at io.debezium.connector.mysql.AbstractReader.wrap(AbstractReader.java:241) connect_1 | at io.debezium.connector.mysql.AbstractReader.failed(AbstractReader.java:218) connect_1 | at io.debezium.connector.mysql.BinlogReader.handleEvent(BinlogReader.java:607) connect_1 | at com.github.shyiko.mysql.binlog.BinaryLogClient.notifyEventListeners(BinaryLogClient.java:1104) connect_1 | at com.github.shyiko.mysql.binlog.BinaryLogClient.listenForEventPackets(BinaryLogClient.java:955) connect_1 | at com.github.shyiko.mysql.binlog.BinaryLogClient.connect(BinaryLogClient.java:595) connect_1 | at com.github.shyiko.mysql.binlog.BinaryLogClient$7.run(BinaryLogClient.java:839) connect_1 | at java.base/java.lang.Thread.run(Thread.java:834) connect_1 | Caused by: java.time.format.DateTimeParseException: Text '123' could not be parsed at index 0{code}
 
 
*123* Is not a valid value for DATE field, but MySQL accepts this alter query and sets default value to {{2020-01-23}}

Start by reproducing the MySQL ALTER TABLE statement that sets a DATE default to 123, then trace the Debezium MySQL connector from binlog event handling through DATE default parsing. Compare the connector's behavior with MySQL's accepted default value; done means the connector no longer fails on this schema change and handles the resulting DATE value consistently.

Written by the indexing model from the issue text.