Spring examples use old fallover plugin

[jasonab]

Describe the issue

Many of the Spring examples use the old failover plugin, as well as deprecated properties (such as keepSessionStateOnFailover). It would be very helpful if the examples corresponded to the current documentation.

Links

https://github.com/aws/aws-advanced-jdbc-wrapper/blob/main/examples/SpringTxFailoverExample/src/main/resources/application.yml

https://github.com/aws/aws-advanced-jdbc-wrapper/blob/main/examples/SpringBootHikariExample/src/main/resources/application.yml