jdbc connection validation

There is a validate method:  https://github.com/debezium/debezium/blob/d11510cd2b394e69b930ce73151378b9a89ee7b2/debezium-core/src/main/java/io/debezium/jdbc/JdbcConnection.java#L882

but the connection only checks if it's connected: https://github.com/debezium/debezium/blob/d11510cd2b394e69b930ce73151378b9a89ee7b2/debezium-core/src/main/java/io/debezium/jdbc/JdbcConnection.java#L890

Sadly due to security reasons the connections are terminated overnight and the isconnected is not enough to verify the connection - the validate does however solve our problems. I can imagine other scenarios that the is valid would be more useful and is the normal strategy for most pooling libraries.

Please can we replace the isConnected with isValid

If it helps: https://github.com/debezium/debezium/pull/2994