SpringBoot Support setting KafkaAdmin#operationTimeout via externalised configuration

I have a Spring Boot application that makes use of Kafka via spring-kafka. Recently I have started observing timeouts while trying to fetch administrative data from Kafka using the KafkaAdmin class. To solve this I would like to set the operationTimeout property of KafkaAdmin via an externalised property like how modifyTopicConfigs or fatalIfBrokerNotAvailable properties are set. At present the only way to override the default value is to explicitly call the setter with the desired value from the application. Although this isn't much of a hassle it would be convenient if the auto configuration can automatically set the provided value from an externalised source like a YAML or properties file.

Comment From: wilkinsona

Closing in favor of #33288. Thanks for the PR, @terminux!