(JAVA SPRING RESTCLIENT)Fix missing imports when using withXml for Spring RestClient and fix its README

[Nicklas2751]

This PR fixes #19137 by adding the missing imports for "withXML" for the Spring 6 RestClient.
It also fixes the example in the generated README of the RestClient.

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[welshm]

This change looks fine to me - however it's not JavaSpring specific, it's just the Java rest-client in general.

[Nicklas2751]

This change looks fine to me - however it's not JavaSpring specific, it's just the Java rest-client in general.

@welshm The client I changed is the Spring RestClient which came with Spring 6.1: https://spring.io/blog/2023/07/13/new-in-spring-6-1-restclient and the other Java Clients don‘t have this issue or what do you mean?

[welshm]

This change looks fine to me - however it's not JavaSpring specific, it's just the Java rest-client in general.

@welshm The client I changed is the Spring RestClient which came with Spring 6.1: https://spring.io/blog/2023/07/13/new-in-spring-6-1-restclient and the other Java Clients don‘t have this issue or what do you mean?

Sorry my mistake - I was looking at the file paths - it just says rest client and makes no mention of Spring.

Change looks good to me